现在我有了这个片段,我想使用setContentView,但到目前为止我还不知道如何使用。你可以在下面的代码中看到我的情况,我不试图膨胀布局,我试图使用它的视图称为SampleView。那么我该怎么做呢?
public class largeImageScroller extends SherlockFragment {
// Physical display width and height.
private static int displayWidth = 0;
private static int displayHeight = 0;
/** Called when the activity is first created. */
public View onCreateView(LayoutInflater inflater, ViewGroup group, Bundle saved) {
getActivity();
// displayWidth and displayHeight will change depending on screen
// orientation. To get these dynamically, we should hook onSizeChanged().
// This simple example uses only landscape mode, so it's ok to get them
// once on startup and use those values throughout.
Display display = ((WindowManager)
getActivity().getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay();
displayWidth = display.getWidth();
displayHeight = display.getHeight();
// SampleView constructor must be constructed last as it needs the
// displayWidth and displayHeight we just got.
setContentView(new SampleView(this));
}
private static class SampleView extends View {
private static Bitmap bmLargeImage; //bitmap large enough to be scrolled
private static Rect displayRect = null; //rect we display to
private Rect scrollRect = null; //rect we scroll over our bitmap with
private int scrollRectX = 0; //current left location of scroll rect
private int scrollRectY = 0; //current top location of scroll rect
private float scrollByX = 0; //x amount to scroll by
private float scrollByY = 0; //y amount to scroll by
private float startX = 0; //track x from one ACTION_MOVE to the next
private float startY = 0; //track y from one ACTION_MOVE to the next
public SampleView(Context context) {
super(context);
// Destination rect for our main canvas draw. It never changes.
displayRect = new Rect(0, 0, displayWidth, displayHeight);
// Scroll rect: this will be used to 'scroll around' over the
// bitmap in memory. Initialize as above.
scrollRect = new Rect(0, 0, displayWidth, displayHeight);
// Load a large bitmap into an offscreen area of memory.
bmLargeImage = BitmapFactory.decodeResource(getResources(),
R.drawable.ground_floor_b);
}
@Override
public boolean onTouchEvent(MotionEvent event) {
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
// Remember our initial down event location.
startX = event.getRawX();
startY = event.getRawY();
break;
case MotionEvent.ACTION_MOVE:
float x = event.getRawX();
float y = event.getRawY();
// Calculate move update. This will happen many times
// during the course of a single movement gesture.
scrollByX = x - startX; //move update x increment
scrollByY = y - startY; //move update y increment
startX = x; //reset initial values to latest
startY = y;
invalidate(); //force a redraw
break;
}
return true; //done with this event so consume it
}
@Override
protected void onDraw(Canvas canvas) {
// Our move updates are calculated in ACTION_MOVE in the opposite direction
// from how we want to move the scroll rect. Think of this as dragging to
// the left being the same as sliding the scroll rect to the right.
int newScrollRectX = scrollRectX - (int)scrollByX;
int newScrollRectY = scrollRectY - (int)scrollByY;
// Don't scroll off the left or right edges of the bitmap.
if (newScrollRectX < 0)
newScrollRectX = 0;
else if (newScrollRectX > (bmLargeImage.getWidth() - displayWidth))
newScrollRectX = (bmLargeImage.getWidth() - displayWidth);
// Don't scroll off the top or bottom edges of the bitmap.
if (newScrollRectY < 0)
newScrollRectY = 0;
else if (newScrollRectY > (bmLargeImage.getHeight() - displayHeight))
newScrollRectY = (bmLargeImage.getHeight() - displayHeight);
// We have our updated scroll rect coordinates, set them and draw.
scrollRect.set(newScrollRectX, newScrollRectY,
newScrollRectX + displayWidth, newScrollRectY + displayHeight);
Paint paint = new Paint();
canvas.drawBitmap(bmLargeImage, scrollRect, displayRect, paint);
// Reset current scroll coordinates to reflect the latest updates,
// so we can repeat this update process.
scrollRectX = newScrollRectX;
scrollRectY = newScrollRectY;
}
}
}
5条答案
按热度按时间qlfbtfca1#
您不需要分段调用
setContentView
,实际上您需要从onCreateView
返回一个View
。尝试替换:
用这个:
jtjikinw2#
返回要使用的视图示例:
jq6vz3qz3#
另外,从
onCreateView()
调用getActivity()
是不安全的。确保在onActivityCreated()
中或之后调用它,因为此时您的Fragment
与Activity
完全关联。检查Fragment
的生命周期。Fragments
ezykj2lf4#
如前所述,如果出现碎片,你需要返回视图,但是如果你想像
setContentView()
一样使用它,你可以按照下面的方式来做。1.将此代码片段放在必须放置
setContentView()
的位置2.现在,如果您想从xml文件访问某些内容,可以使用
3.在
OnCreateView()
的末尾,您必须将完整示例:
wr98u20j5#
在活动中,我们需要使用
setContentView(R.layout.main)
设置视图在片段中,我们需要覆盖
onCreateView()
来设置所需的视图。