Question

我有一个名为ZoomControlBar的自定义UI组件，它使用一个名为zoom_slider_bar的drawable。当我在XML中使用该组件时，我收到以下错误：

  AndroidRuntime(8137): Caused by: android.content.res.Resources$NotFoundException: 
  File res/drawable/zoom_slider_bar.xml from drawable resource ID #0x7f02000a
  AndroidRuntime(8137):     at 
  android.content.res.Resources.loadDrawable(Resources.java:2091)
  AndroidRuntime(8137):     at 
  android.content.res.Resources.getDrawable(Resources.java:695)
  AndroidRuntime(8137):     at android.view.View.setBackgroundResource(View.java:14758)
  AndroidRuntime(8137):     at com.example.newcameraproject.ZoomControlBar.<init>
  (ZoomControlBar.java:30)
  AndroidRuntime(8137):     ... 31 more
  AndroidRuntime(8137): Caused by: java.lang.NullPointerException
  AndroidRuntime(8137):     at 
  android.graphics.drawable.DrawableContainer  
  $DrawableContainerState.addChild(DrawableContainer.java:527)
  AndroidRuntime(8137):     at 
  android.graphics.drawable.StateListDrawable
  $StateListState.addStateSet(StateListDrawable.java:288)
  AndroidRuntime(8137):     at 
  android.graphics.drawable.StateListDrawable.inflate(StateListDrawable.java:186)
  AndroidRuntime(8137):     at 
  android.graphics.drawable.Drawable.createFromXmlInner(Drawable.java:901)
  AndroidRuntime(8137):     at 
  android.graphics.drawable.Drawable.createFromXml(Drawable.java:837)
  AndroidRuntime(8137):     at 
  android.content.res.Resources.loadDrawable(Resources.java:2087)
  AndroidRuntime(8137):     ... 34 more

这是ZoomControlBar：

  public class ZoomControlBar extends ZoomControl {
private static final String TAG="ZoomControlBar";
private static int THRESHOLD_FIRST_MOVE;
private static int ICON_SPACING;

private View mBar;
private boolean mStartChanging;
private int mSliderLength;
private int mHeight;
private int mIconHeight;
private int mTotalIconHeight;

public ZoomControlBar(Context c,AttributeSet attrs)
{
    super(c,attrs);
    THRESHOLD_FIRST_MOVE=dpToPixel(c, 10);
    ICON_SPACING=dpToPixel(c,12);
    mBar=new View(c);
    mBar.setBackgroundResource(R.drawable.zoom_slider_bar);
    addView(mBar);
}

@Override
public void setActivated(boolean activated)
{
    super.setActivated(activated);
    mBar.setActivated(activated);
}

private int getSliderPosition(int y)
{
    int pos;//relative position in the slider
    if(mDegree==180)
        pos=mHeight-mTotalIconHeight;
    else
        pos=mHeight-mTotalIconHeight-y;
    if(pos<0)
        pos=0;
    if(pos>mSliderLength)
        pos=mSliderLength;
    return pos;
}

@Override
protected void onSizeChanged(int w,int h,int oldW,int oldH)
{
      mHeight = h;
        mIconHeight = mZoomIn.getMeasuredHeight();
        mTotalIconHeight = mIconHeight + ICON_SPACING;
        mSliderLength = mHeight - (2 * mTotalIconHeight);
}

@TargetApi(Build.VERSION_CODES.HONEYCOMB)
@Override
public boolean dispatchTouchEvent(MotionEvent event) {
    if (!isEnabled() || (mHeight == 0)) return false;
    int action = event.getAction();

    switch (action) {
        case MotionEvent.ACTION_OUTSIDE:
        case MotionEvent.ACTION_CANCEL:
        case MotionEvent.ACTION_UP:
            setActivated(false);
            closeZoomControl();
            break;

        case MotionEvent.ACTION_DOWN:
            setActivated(true);
            mStartChanging = false;
        case MotionEvent.ACTION_MOVE:
            int pos = getSliderPosition((int) event.getY());
            if (!mStartChanging) {
                // Make sure the movement is large enough before we start
                // changing the zoom.
                int delta = mSliderPosition - pos;
                if ((delta > THRESHOLD_FIRST_MOVE) ||
                        (delta < -THRESHOLD_FIRST_MOVE)) {
                    mStartChanging = true;
                }
            }
            if (mStartChanging) {
                performZoom(1.0d * pos / mSliderLength);
                mSliderPosition = pos;
            }
            requestLayout();
    }
    return true;
}

@Override
public void setDegree(int degree) {
    // layout for the left-hand camera control
    if ((degree == 180) || (mDegree == 180)) requestLayout();
    super.setDegree(degree);
}

@Override
protected void onLayout(
        boolean changed, int left, int top, int right, int bottom) {
    if (mZoomMax == 0) return;
    int width = right - left;
    mBar.layout(0, mTotalIconHeight, width, mHeight - mTotalIconHeight);
    // For left-hand users, as the device is rotated for 180 degree,
    // the zoom-in button should be on the top.
    int pos; // slider position
    int sliderPosition;
    if (mSliderPosition != -1) { // -1 means invalid
        sliderPosition = mSliderPosition;
    } else {
        sliderPosition = (int) ((double) mSliderLength * mZoomIndex / mZoomMax);
    }
    if (mDegree == 180) {
        mZoomOut.layout(0, 0, width, mIconHeight);
        mZoomIn.layout(0, mHeight - mIconHeight, width, mHeight);
        pos = mBar.getTop() + sliderPosition;
    } else {
        mZoomIn.layout(0, 0, width, mIconHeight);
        mZoomOut.layout(0, mHeight - mIconHeight, width, mHeight);
        pos = mBar.getBottom() - sliderPosition;
    }
    int sliderHeight = mZoomSlider.getMeasuredHeight();
    mZoomSlider.layout(0, (pos - sliderHeight / 2),
            width, (pos + sliderHeight / 2));
}

@Override
public void setZoomIndex(int index) {
    super.setZoomIndex(index);
    mSliderPosition = -1; // -1 means invalid
    requestLayout();
}

private int dpToPixel(Context c,int dp)
{
    DisplayMetrics metrics=new DisplayMetrics();
    WindowManager wm=(WindowManager)c.getSystemService(Context.WINDOW_SERVICE);
    wm.getDefaultDisplay().getMetrics(metrics);
    float pixelDensity=metrics.density;
    return Math.round(dp*pixelDensity);
}
}

将背景drawable设置为：

时出现错误

 mBar.setBackgroundResource(R.drawable.zoom_slider_bar);

这是我的抽签：

<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_activated="true" android:drawable="@drawable/ic_zoom_big" />
<item android:drawable="@drawable/ic_zoom_big_dark" />
</selector>

我将这9个补丁图片ic_zoom_big，ic_zoom_big_dark添加到drawable-hdpi

Answer 1

将zoom_slider_bar.xml放入普通drawable文件夹而不是文件夹后再试一次，具体取决于drawable-mdpi等屏幕大小。如果你还没有，那就创建它。 [没有任何后缀]

这解决了我前段时间遇到的类似问题。

Drawable不能膨胀

1 个答案: