Example usage for android.view SurfaceHolder lockCanvas

Introduction

In this page you can find the example usage for android.view SurfaceHolder lockCanvas.

Prototype

public Canvas lockCanvas();

Source Link

Document

Start editing the pixels in the surface.

Usage

From source file:com.android.screenspeak.contextmenu.RadialMenuView.java

@Override
public void invalidate() {
    super.invalidate();

    final SurfaceHolder holder = mHolder;
    if (holder == null) {
        return;//w w w  .ja v a2 s.c  o m
    }

    final Canvas canvas = holder.lockCanvas();
    if (canvas == null) {
        return;
    }

    // Clear the canvas.
    canvas.drawColor(Color.TRANSPARENT, Mode.CLEAR);

    if (getVisibility() != View.VISIBLE) {
        holder.unlockCanvasAndPost(canvas);
        return;
    }

    final int width = getWidth();
    final int height = getHeight();

    if (!mDisplayWedges) {
        mCenter.x = (width / 2.0f);
        mCenter.y = (height / 2.0f);
    }

    // Draw the pretty gradient background.
    mGradientBackground.setGradientCenter((mCenter.x / width), (mCenter.y / height));
    mGradientBackground.setBounds(0, 0, width, height);
    mGradientBackground.draw(canvas);

    final RadialMenu menu = (mSubMenu != null) ? mSubMenu : mRootMenu;
    final float center = mExtremeRadius;

    if (mDisplayWedges) {
        final int wedges = menu.size();
        final float degrees = 360.0f / wedges;

        // Refresh cached wedge shapes if necessary.
        if (0 != menu.size()) {
            invalidateCachedWedgeShapes();
        }

        // Draw the cancel dot.
        drawCancel(canvas);

        // Draw wedges.
        for (int i = 0; i < wedges; i++) {
            drawWedge(canvas, center, i, menu, degrees);
        }
    } else {
        // Draw the center dot.
        drawCenterDot(canvas, width, height);
    }

    // Draw corners.
    for (int i = 0; i < 4; i++) {
        drawCorner(canvas, width, height, center, i);
    }

    holder.unlockCanvasAndPost(canvas);
}

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From source file:com.googlecode.eyesfree.widget.RadialMenuView.java

@Override
public void invalidate() {
    super.invalidate();

    final SurfaceHolder holder = mHolder;
    if (holder == null) {
        return;/*from  ww  w .  ja va  2  s  .c  o m*/
    }

    final Canvas canvas = holder.lockCanvas();
    if (canvas == null) {
        return;
    }

    // Clear the canvas.
    canvas.drawColor(Color.TRANSPARENT, Mode.CLEAR);

    if (getVisibility() != View.VISIBLE) {
        holder.unlockCanvasAndPost(canvas);
        return;
    }

    final int width = getWidth();
    final int height = getHeight();

    if (!mDisplayWedges) {
        mCenter.x = (width / 2.0f);
        mCenter.y = (height / 2.0f);
    }

    // Draw the pretty gradient background.
    mGradientBackground.setGradientCenter((mCenter.x / width), (mCenter.y / height));
    mGradientBackground.setBounds(0, 0, width, height);
    mGradientBackground.draw(canvas);

    final RadialMenu menu = (mSubMenu != null) ? mSubMenu : mRootMenu;
    final float center = mExtremeRadius;

    if (mDisplayWedges) {
        final int wedges = menu.size();
        final float degrees = 360.0f / wedges;

        // Refresh cached wedge shapes if necessary.
        if (mCachedMenuSize != menu.size()) {
            invalidateCachedWedgeShapes();
        }

        // Draw the cancel dot.
        drawCancel(canvas, width, height, center);

        // Draw wedges.
        for (int i = 0; i < wedges; i++) {
            drawWedge(canvas, width, height, center, i, menu, degrees);
        }
    } else {
        // Draw the center dot.
        drawCenterDot(canvas, width, height);
    }

    // Draw corners.
    for (int i = 0; i < 4; i++) {
        drawCorner(canvas, width, height, center, i);
    }

    holder.unlockCanvasAndPost(canvas);
}

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