Verwendung von isInEditMode () zum Anzeigen des Layouts mit benutzerdefinierter Ansicht im Editor

Ich muss eine Software mit einer benutzerdefinierten Ansicht bearbeiten. Wenn ich versuche, Layout-XML zu bearbeiten, sagt Eclipse:

Verwenden Sie View.isInEditMode () in Ihren benutzerdefinierten Ansichten, um Code zu überspringen, wenn er in Eclipse angezeigt wird

Ich habe jedoch keine Ahnung, wie und wo ich isInEditMode () in der App verwenden muss

Meine XML-Datei ist

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 
     xmlns:android="http://schemas.android.com/apk/res/android"
     android:orientation="vertical"
     android:layout_width="fill_parent"
     android:layout_height="fill_parent"
     android:background="#ff000000"
    >
<TextView
     android:id="@+id/result"
     android:layout_width="fill_parent" 
     android:layout_height="wrap_content"
     android:gravity="right"
     android:textSize="32dip"
     android:scrollbars="none"
     android:lines="1"
     android:freezesText="true"
     android:textColor="@color/result"
    />
<EditText
     android:id="@+id/input"
     android:layout_width="fill_parent"
     android:layout_height="wrap_content"
     android:gravity="left"
     android:textSize="28dip"
     android:scrollbars="none"
     android:singleLine="true"
     android:autoText="false"
     android:imeOptions="flagNoEnterAction|flagNoExtractUi"
     />
<ListView
     android:id="@+id/history"
     android:layout_width="fill_parent"
     android:layout_height="0dip"
     android:layout_weight="1"
     android:cacheColorHint="#ff000000"
     android:choiceMode="singleChoice"
     android:scrollbarStyle="outsideInset"
     android:scrollbars="none"
    />
<calculator.GraphView
     android:id="@+id/graph"
     android:layout_width="fill_parent"
     android:layout_height="0dip"
     android:layout_weight="1"
     android:visibility="gone"
     />
<include layout="@layout/keyboard" />
</LinearLayout>

Und mein GraphView ist

public class GraphView extends View implements Grapher,
        ZoomButtonsController.OnZoomListener,
        TouchHandler.TouchHandlerInterface {
    private int width, height;
    private Matrix matrix = new Matrix();
    private Paint paint = new Paint();
    private Paint textPaint = new Paint();
    private ArrayList<Function> funcs = new ArrayList<Function>();
    private Data next = new Data(), endGraph = new Data();
    private Data graphs[] = { new Data(), new Data(), new Data(), new Data(),
            new Data() };
    private static final int GRAPHS_SIZE = 5;
    private float gwidth = 8;
    private float currentX, currentY;
    private float lastMinX;
    private Scroller scroller;
    private float boundMinY, boundMaxY;
    protected ZoomButtonsController zoomController = new ZoomButtonsController(
            this);
    private ZoomTracker zoomTracker = new ZoomTracker();
    private TouchHandler touchHandler;
    private float lastTouchX, lastTouchY;

    private static final int COL_AXIS = 0xff00a000, COL_GRID = 0xff004000,
            COL_TEXT = 0xff00ff00;

    private static final int COL_GRAPH[] = { 0xffffffff, 0xff00ffff,
            0xffffff00, 0xffff00ff, 0xff80ff80 };

    public GraphView(Context context, AttributeSet attrs) {
        super(context, attrs);
        init(context);
    }

    public GraphView(Context context) {
        super(context);
        touchHandler = new TouchHandler(this);
        init(context);
    }

    private void init(Context context) {
        zoomController.setOnZoomListener(this);
        scroller = new Scroller(context);
        paint.setAntiAlias(false);
        textPaint.setAntiAlias(true);
    }

    @SuppressLint("WrongCall")
    public String captureScreenshot() {
        Bitmap bitmap = Bitmap.createBitmap(width, height,
                Bitmap.Config.RGB_565);
        Canvas canvas = new Canvas(bitmap);
        onDraw(canvas);
        return Util.saveBitmap(bitmap, Grapher.SCREENSHOT_DIR, "calculator");
    }

    private void clearAllGraph() {
        for (int i = 0; i < GRAPHS_SIZE; ++i) {
            graphs[i].clear();
        }
    }

    public void setFunctions(ArrayList<Function> fs) {
        funcs.clear();
        for (Function f : fs) {
            int arity = f.arity();
            if (arity == 0 || arity == 1) {
                funcs.add(f);
            }
        }
        clearAllGraph();
        invalidate();
    }

    public void setFunction(Function f) {
        funcs.clear();
        if (f != null) {
            funcs.add(f);
        }
        clearAllGraph();
        invalidate();
    }

    public void onVisibilityChanged(boolean visible) {
    }

    public void onZoom(boolean zoomIn) {
        if (zoomIn) {
            if (canZoomIn()) {
                gwidth /= 2;
                invalidateGraphs();
            }
        } else {
            if (canZoomOut()) {
                gwidth *= 2;
                invalidateGraphs();
            }
        }
        zoomController.setZoomInEnabled(canZoomIn());
        zoomController.setZoomOutEnabled(canZoomOut());
    }

    public void onResume() {
    }

    public void onPause() {
    }

    public void onDetachedFromWindow() {
        zoomController.setVisible(false);
        super.onDetachedFromWindow();
    }

    protected void onSizeChanged(int w, int h, int ow, int oh) {
        width = w;
        height = h;
        clearAllGraph();
    }

    protected void onDraw(Canvas canvas) {
        if (funcs.size() == 0) {
            return;
        }
        if (scroller.computeScrollOffset()) {
            final float scale = gwidth / width;
            currentX = scroller.getCurrX() * scale;
            currentY = scroller.getCurrY() * scale;
            if (!scroller.isFinished()) {
                invalidate();
            }
        }
        drawGraph(canvas);
    }

    private float eval(Function f, float x) {
        float v = (float) f.eval(x);

        if (v < -10000f) {
            return -10000f;
        }
        if (v > 10000f) {
            return 10000f;
        }
        return v;
    }

    private float distance2(float x1, float y1, float x2, float y2, float y) {
        final float dx = x2 - x1;
        final float dy = y2 - y1;
        final float up = dx * (y1 + y2 - y - y);
        return up * up / (dx * dx + dy * dy);
    }

    private void computeGraph(Function f, float minX, float maxX, float minY,
            float maxY, Data graph) {
        if (f.arity() == 0) {
            float v = (float) f.eval();
            if (v < -10000f) {
                v = -10000f;
            }
            if (v > 10000f) {
                v = 10000f;
            }
            graph.clear();
            graph.push(minX, v);
            graph.push(maxX, v);
            return;
        }

        final float scale = width / gwidth;
        final float maxStep = 15.8976f / scale;
        final float minStep = .05f / scale;
        float ythresh = 1 / scale;
        ythresh = ythresh * ythresh;
        if (!graph.empty()) {
            if (minX >= lastMinX) {
                graph.eraseBefore(minX);
            } else {
                graph.eraseAfter(maxX);
                maxX = Math.min(maxX, graph.firstX());
                graph.swap(endGraph);
            }
        }
        if (graph.empty()) {
            graph.push(minX, eval(f, minX));
        }
        float leftX, leftY;
        float rightX = graph.topX(), rightY = graph.topY();
        int nEval = 1;
        while (true) {
            leftX = rightX;
            leftY = rightY;
            if (leftX > maxX) {
                break;
            }
            if (next.empty()) {
                float x = leftX + maxStep;
                next.push(x, eval(f, x));
                ++nEval;
            }
            rightX = next.topX();
            rightY = next.topY();
            next.pop();

            if (leftY != leftY && rightY != rightY) { // NaN
                continue;
            }

            float dx = rightX - leftX;
            float middleX = (leftX + rightX) / 2;
            float middleY = eval(f, middleX);
            ++nEval;
            boolean middleIsOutside = (middleY < leftY && middleY < rightY)
                    || (leftY < middleY && rightY < middleY);
            if (dx < minStep) {
                if (middleIsOutside) {
                    graph.push(rightX, Float.NaN);
                }
                graph.push(rightX, rightY);
                continue;
            }
            if (middleIsOutside
                    && ((leftY < minY && rightY > maxY) || (leftY > maxY && rightY < minY))) {
                graph.push(rightX, Float.NaN);
                graph.push(rightX, rightY);
                continue;
            }

            if (!middleIsOutside) {

                if (distance2(leftX, leftY, rightX, rightY, middleY) < ythresh) {
                    graph.push(rightX, rightY);
                    continue;
                }
            }
            next.push(rightX, rightY);
            next.push(middleX, middleY);
            rightX = leftX;
            rightY = leftY;
        }
        if (!endGraph.empty()) {
            graph.append(endGraph);
        }
        long t2 = System.currentTimeMillis();

        next.clear();
        endGraph.clear();
    }

    private static Path path = new Path();

    private Path graphToPath(Data graph) {
        boolean first = true;
        int size = graph.size;
        float[] xs = graph.xs;
        float[] ys = graph.ys;
        path.rewind();
        for (int i = 0; i < size; ++i) {
            float y = ys[i];
            float x = xs[i];
            // Calculator.log("path " + x + ' ' + y);
            if (y == y) { // !NaN
                if (first) {
                    path.moveTo(x, y);
                    first = false;
                } else {
                    path.lineTo(x, y);
                }
            } else {
                first = true;
            }
        }
        return path;
    }

    private static final float NTICKS = 15;

    private static float stepFactor(float w) {
        float f = 1;
        while (w / f > NTICKS) {
            f *= 10;
        }
        while (w / f < NTICKS / 10) {
            f /= 10;
        }
        float r = w / f;
        if (r < NTICKS / 5) {
            return f / 5;
        } else if (r < NTICKS / 2) {
            return f / 2;
        } else {
            return f;
        }
    }

    private static StringBuilder b = new StringBuilder();
    private static char[] buf = new char[20];

    private static StringBuilder format(float fv) {
        int pos = 0;
        boolean addDot = false;
        int v = Math.round(fv * 100);
        boolean isNeg = v < 0;
        v = isNeg ? -v : v;
        for (int i = 0; i < 2; ++i) {
            int digit = v % 10;
            v /= 10;
            if (digit != 0 || addDot) {
                buf[pos++] = (char) ('0' + digit);
                addDot = true;
            }
        }
        if (addDot) {
            buf[pos++] = '.';
        }
        if (v == 0) {
            buf[pos++] = '0';
        }
        while (v != 0) {
            buf[pos++] = (char) ('0' + (v % 10));
            v /= 10;
        }
        if (isNeg) {
            buf[pos++] = '-';
        }
        b.setLength(0);
        b.append(buf, 0, pos);
        b.reverse();
        return b;
    }

    private void drawGraph(Canvas canvas) {
        long t1 = System.currentTimeMillis();
        float minX = currentX - gwidth / 2;
        float maxX = minX + gwidth;
        float ywidth = gwidth * height / width;
        float minY = currentY - ywidth / 2;
        float maxY = minY + ywidth;
        if (minY < boundMinY || maxY > boundMaxY) {
            float halfw = ywidth / 2;
            boundMinY = minY - halfw;
            boundMaxY = maxY + halfw;
            clearAllGraph();
        }

        canvas.drawColor(0xff000000);

        paint.setStrokeWidth(0);
        paint.setAntiAlias(false);
        paint.setStyle(Paint.Style.STROKE);

        final float h2 = height / 2f;
        final float scale = width / gwidth;

        float x0 = -minX * scale;
        boolean drawYAxis = true;
        if (x0 < 25) {
            x0 = 25;
            // drawYAxis = false;
        } else if (x0 > width - 3) {
            x0 = width - 3;
            // drawYAxis = false;
        }
        float y0 = maxY * scale;
        if (y0 < 3) {
            y0 = 3;
        } else if (y0 > height - 15) {
            y0 = height - 15;
        }

        final float tickSize = 3;
        final float y2 = y0 + tickSize;
        paint.setColor(COL_GRID);
        float step = stepFactor(gwidth);
        float v = ((int) (minX / step)) * step;
        textPaint.setColor(COL_TEXT);
        textPaint.setTextSize(12);
        textPaint.setTextAlign(Paint.Align.CENTER);
        float stepScale = step * scale;
        for (float x = (v - minX) * scale; x <= width; x += stepScale, v += step) {
            canvas.drawLine(x, 0, x, height, paint);
            if (!(-.001f < v && v < .001f)) {
                StringBuilder b = format(v);
                canvas.drawText(b, 0, b.length(), x, y2 + 10, textPaint);
            }
        }

        final float x1 = x0 - tickSize;
        v = ((int) (minY / step)) * step;
        textPaint.setTextAlign(Paint.Align.RIGHT);
        for (float y = height - (v - minY) * scale; y >= 0; y -= stepScale, v += step) {
            canvas.drawLine(0, y, width, y, paint);
            if (!(-.001f < v && v < .001f)) {
                StringBuilder b = format(v);
                canvas.drawText(b, 0, b.length(), x1, y + 4, textPaint);
            }
        }

        paint.setColor(COL_AXIS);
        if (drawYAxis) {
            canvas.drawLine(x0, 0, x0, height, paint);
        }
        canvas.drawLine(0, y0, width, y0, paint);

        matrix.reset();
        matrix.preTranslate(-currentX, -currentY);
        matrix.postScale(scale, -scale);
        matrix.postTranslate(width / 2, height / 2);

        paint.setStrokeWidth(0);
        paint.setAntiAlias(false);

        int n = Math.min(funcs.size(), GRAPHS_SIZE);
        for (int i = 0; i < n; ++i) {
            computeGraph(funcs.get(i), minX, maxX, boundMinY, boundMaxY,
                    graphs[i]);
            Path path = graphToPath(graphs[i]);
            path.transform(matrix);
            paint.setColor(COL_GRAPH[i]);
            canvas.drawPath(path, paint);
        }
        lastMinX = minX;
    }

    private boolean canZoomIn() {
        return gwidth > 1f;
    }

    private boolean canZoomOut() {
        return gwidth < 50;
    }

    private void invalidateGraphs() {
        clearAllGraph();
        boundMinY = boundMaxY = 0;
        invalidate();
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        return touchHandler != null ? touchHandler.onTouchEvent(event) : super
                .onTouchEvent(event);
    }

    public void onTouchDown(float x, float y) {
        zoomController.setVisible(true);
        if (!scroller.isFinished()) {
            scroller.abortAnimation();
        }
        lastTouchX = x;
        lastTouchY = y;
    }

    public void onTouchMove(float x, float y) {
        float deltaX = x - lastTouchX;
        float deltaY = y - lastTouchY;
        if (deltaX < -1 || deltaX > 1 || deltaY < -1 || deltaY > 1) {
            scroll(-deltaX, deltaY);
            lastTouchX = x;
            lastTouchY = y;
            invalidate();
        }
    }

    public void onTouchUp(float x, float y) {
        final float scale = width / gwidth;
        float sx = -touchHandler.velocityTracker.getXVelocity();
        float sy = touchHandler.velocityTracker.getYVelocity();
        final float asx = Math.abs(sx);
        final float asy = Math.abs(sy);
        if (asx < asy / 3) {
            sx = 0;
        } else if (asy < asx / 3) {
            sy = 0;
        }
        scroller.fling(Math.round(currentX * scale),
                Math.round(currentY * scale), Math.round(sx), Math.round(sy),
                -10000, 10000, -10000, 10000);
        invalidate();
    }

    public void onTouchZoomDown(float x1, float y1, float x2, float y2) {
        zoomTracker.start(gwidth, x1, y1, x2, y2);
    }

    public void onTouchZoomMove(float x1, float y1, float x2, float y2) {
        if (!zoomTracker.update(x1, y1, x2, y2)) {
            return;
        }
        float targetGwidth = zoomTracker.value;
        if (targetGwidth > .25f && targetGwidth < 200) {
            gwidth = targetGwidth;
        }
        invalidateGraphs();
    }

    private void scroll(float deltaX, float deltaY) {
        final float scale = gwidth / width;
        float dx = deltaX * scale;
        float dy = deltaY * scale;
        final float adx = Math.abs(dx);
        final float ady = Math.abs(dy);
        if (adx < ady / 3) {
            dx = 0;
        } else if (ady < adx / 3) {
            dy = 0;
        }
        currentX += dx;
        currentY += dy;
    }
}

Das Fehlerprotokoll des XML-Editors

java.lang.NullPointerException
    at android.widget.ZoomButtonsController.createContainer(ZoomButtonsController.java:266)
    at android.widget.ZoomButtonsController.<init>(ZoomButtonsController.java:212)
    at calculator.GraphView.<init>(GraphView.java:43)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(    at sun.reflect.NativeConstructorAccessorImpl.newInstance(    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(    at java.lang.reflect.Constructor.newInstance(    at com.android.ide.eclipse.adt.internal.editors.layout.ProjectCallback.instantiateClass(ProjectCallback.java:422)
    at com.android.ide.eclipse.adt.internal.editors.layout.ProjectCallback.loadView(ProjectCallback.java:179)
    at android.view.BridgeInflater.loadCustomView(BridgeInflater.java:207)
    at android.view.BridgeInflater.createViewFromTag(BridgeInflater.java:135)
    at android.view.LayoutInflater.rInflate_Original(LayoutInflater.java:746)
    at android.view.LayoutInflater_Delegate.rInflate(LayoutInflater_Delegate.java:64)
    at android.view.LayoutInflater.rInflate(LayoutInflater.java:718)
    at android.view.LayoutInflater.inflate(LayoutInflater.java:489)
    at android.view.LayoutInflater.inflate(LayoutInflater.java:372)

isInEditMode()sollte im Konstruktor der benutzerdefinierten Ansicht verwendet werden. Versuchen Sie den folgenden Code:

     public class GraphView extends View implements Grapher
        {

         public GraphView(Context context, AttributeSet attrs) {
                super(context, attrs);
                if(!isInEditMode())
                 init(context);
            }

            public GraphView(Context context) {
                super(context);
               if(!isInEditMode()){
                touchHandler = new TouchHandler(this);
                init(context);
              }
            }

public class CustomTextView extends TextView {

public CustomTextView(Context context) {
    super(context);
}

public CustomTextView(Context context, AttributeSet attrs) {
    super(context, attrs);

    if (!isInEditMode()) {
        createTypeface(context, attrs); //whatever added functionality you are trying to add to Widget, call that inside this condition. 
    }

}

public CustomTextView(Context context, AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);
}


//Typeface I wan to set to my Custom TextView It can be any other functionality of your choice

private void createTypeface(Context context, AttributeSet attrs) {

    TypedArray styledAttrs = context.obtainStyledAttributes(attrs,
            R.styleable.CustomTextView);
    String fontName = styledAttrs
            .getString(R.styleable.CustomTextView_Typeface);
    styledAttrs.recycle();

    if (fontName != null) {
        Typeface typeface = Typeface.createFromAsset(context.getAssets(),
                "fonts/" + fontName);

        setTypeface(typeface);
        styledAttrs.recycle();
    }
}

}

Die folgenden Klassen konnten nicht instanziiert werden: - com.google.android.gms.ads.AdView (Klasse öffnen, Ausnahme anzeigen, Cache löschen)

Tipp: Verwenden Sie View.isInEditMode () in Ihren benutzerdefinierten Ansichten, um Code zu überspringen oder Beispieldaten anzuzeigen, wenn diese in der IDE angezeigt werden. Wenn dies ein unerwarteter Fehler ist, können Sie auch versuchen, das Projekt zu erstellen, und dann das Layout manuell aktualisieren.

Exception Details java.lang.NoClassDefFoundError: 
    com/google/android/gms/ads/R$styleable   at 
    com.google.android.gms.internal.ads.zzuq.<init>(com.google.android.gms:play-services-ads-lite@@18.3.0:45)   at com.google.android.gms.internal.ads.zzxl.<init>(com.google.android.gms:play-services-ads-lite@@18.3.0:30)   at com.google.android.gms.internal.ads.zzxl.<init>(com.google.android.gms:play-services-ads-lite@@18.3.0:52)   at com.google.android.gms.internal.ads.zzxl.

<init>(com.google.android.gms:play-services-ads-lite@@18.3.0:17)   at com.google.android.gms.ads.BaseAdView.<init>(com.google.android.gms:play-services-ads-lite@@18.3.0:5)   at com.google.android.gms.ads.AdView.<init>(com.google.android.gms:play-services-ads-lite@@18.3.0:4)   at java.lang.reflect.Constructor.newInstance(Constructor.java:423)   at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:730)   at android.view.LayoutInflater.rInflate_Original(LayoutInflater.java:863)   at android.view.LayoutInflater_Delegate.rInflate(LayoutInflater_Delegate.java:72)   at android.view.LayoutInflater.rInflate(LayoutInflater.java:837)   at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:824)   at android.view.LayoutInflater.inflate(LayoutInflater.java:515)   at android.view.LayoutInflater.inflate(LayoutInflater.java:394) Copy stack to clipboard

Versuchen Sie dies, es funktioniert für mich

public class MyOwnTextView extends TextView {

    public MyOwnTextView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        // TODO Auto-generated constructor stub
        isInEditMode();
    }

    public MyOwnTextView(Context context, AttributeSet attrs) {
        super(context, attrs);
        // TODO Auto-generated constructor stub
        isInEditMode();
    }
    public MyOwnTextView(Context context) {
        super(context);
        // TODO Auto-generated constructor stub
        isInEditMode();
    }

    public void setTypeface(Typeface tf, int style) {
        if(!this.isInEditMode()){
        Typeface normalTypeface = Typeface.createFromAsset(getContext().getAssets(), "font/Roboto-Light.ttf");
        Typeface boldTypeface = Typeface.createFromAsset(getContext().getAssets(), "font/Roboto-Light.ttf");

        if (style == Typeface.BOLD) {
            super.setTypeface(boldTypeface/*, -1*/);
        } else {
            super.setTypeface(normalTypeface/*, -1*/);
        }
        }

    }   

}

dann bei der xml

<com.xxxxx.appname.MyOwnTextView

          android:layout_width="fill_parent"
          android:layout_height="fill_parent"

        />