在我的项目中，我在活动中显示图像。当我用两根手指触摸图像时，我将隐藏包含该图像视图的视图。然后在框架布局中，我将添加一个自定义 touchmimage 视图，以便我可以缩放该图像。但是某处出了点问题。我在这里分享我的代码
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.touchfinger"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="15" />
<application
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name=".MainActivity"
android:screenOrientation="portrait"
android:label="@string/title_activity_main" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
布局
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<ImageView
android:id="@+id/close"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="right"
android:src="@drawable/closeicon"
android:visibility="invisible" />
<FrameLayout
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
<FrameLayout
android:id="@+id/frame"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="@android:color/white" >
</FrameLayout>
<LinearLayout
android:id="@+id/linearlayout"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="@android:color/white"
android:gravity="center" >
<ImageView
android:id="@+id/imageView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:longClickable="true"
android:src="@drawable/logo" />
</LinearLayout>
</FrameLayout>
</LinearLayout>
活动
public class MainActivity extends Activity {
String TAG = "Multitouch";
int modeW;
ImageView im, close;
TouchImageView zImg;
LinearLayout linearlayout;
FrameLayout frame;
Bitmap bmp;
static final int NONE = 0;
static final int DRAG = 1;
static final int ZOOM = 2;
int mode = NONE;
float currentX;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
im = (ImageView) findViewById(R.id.imageView1);
close = (ImageView) findViewById(R.id.close);
linearlayout = (LinearLayout) findViewById(R.id.linearlayout);
frame = (FrameLayout) findViewById(R.id.frame);
zImg = new TouchImageView(this);
bmp = BitmapFactory.decodeResource(getApplicationContext()
.getResources(), R.drawable.logo);
if (bmp == null) {
Log.e("Bitmap is null", "Bitmap is null");
} else {
Log.e("Bitmap is not null", "Bitmap is not null");
}
im.setOnTouchListener(new OnTouchListener() {
@Override
public boolean onTouch(View v, MotionEvent event) {
final float X = event.getX();
switch (event.getAction() & MotionEvent.ACTION_MASK) {
case MotionEvent.ACTION_POINTER_DOWN:
modeW = 1;
try {
close.setVisibility(View.VISIBLE);
linearlayout.setVisibility(View.INVISIBLE);
frame.addView(zImg);
zImg.setImageBitmap(bmp);
zImg.setMaxZoom(3f);
} catch (Exception e) {
e.printStackTrace();
}
break;
case MotionEvent.ACTION_DOWN:
modeW = 0;
currentX = X;
zImg.setScaleType(ScaleType.CENTER_INSIDE);
break;
case MotionEvent.ACTION_UP:
if (modeW == 0)
break;
case MotionEvent.ACTION_MOVE:
float currentx = event.getX();
float diff = currentX - currentx;
if (diff > 9.0 || diff < -9.0)
modeW = 2;
break;
}
return true;
}
});
close.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
close.setVisibility(View.GONE);
frame.removeAllViews();
linearlayout.setVisibility(View.VISIBLE);
}
});
}
}
触摸图像视图
public class TouchImageView extends ImageView {
Matrix matrix = new Matrix();
// We can be in one of these 3 states
static final int NONE = 0;
static final int DRAG = 1;
static final int ZOOM = 2;
int mode = NONE;
// Remember some things for zooming
PointF last = new PointF();
PointF start = new PointF();
float minScale = 1f;
float maxScale = 3f;
float[] m;
float redundantXSpace, redundantYSpace;
float width, height;
static final int CLICK = 3;
float saveScale = 1f;
float right, bottom, origWidth, origHeight, bmWidth, bmHeight;
ScaleGestureDetector mScaleDetector;
Context context;
public TouchImageView(Context context) {
super(context);
super.setClickable(true);
this.context = context;
mScaleDetector = new ScaleGestureDetector(context, new ScaleListener());
matrix.setTranslate(1f, 1f);
m = new float[9];
setImageMatrix(matrix);
setScaleType(ScaleType.MATRIX);
setOnTouchListener(new OnTouchListener() {
@Override
public boolean onTouch(View v, MotionEvent event) {
mScaleDetector.onTouchEvent(event);
matrix.getValues(m);
float x = m[Matrix.MTRANS_X];
float y = m[Matrix.MTRANS_Y];
PointF curr = new PointF(event.getX(), event.getY());
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
last.set(event.getX(), event.getY());
start.set(last);
mode = DRAG;
break;
case MotionEvent.ACTION_MOVE:
if (mode == DRAG) {
float deltaX = curr.x - last.x;
float deltaY = curr.y - last.y;
float scaleWidth = Math.round(origWidth * saveScale);
float scaleHeight = Math.round(origHeight * saveScale);
if (scaleWidth < width) {
deltaX = 0;
if (y + deltaY > 0)
deltaY = -y;
else if (y + deltaY < -bottom)
deltaY = -(y + bottom);
} else if (scaleHeight < height) {
deltaY = 0;
if (x + deltaX > 0)
deltaX = -x;
else if (x + deltaX < -right)
deltaX = -(x + right);
} else {
if (x + deltaX > 0)
deltaX = -x;
else if (x + deltaX < -right)
deltaX = -(x + right);
if (y + deltaY > 0)
deltaY = -y;
else if (y + deltaY < -bottom)
deltaY = -(y + bottom);
}
matrix.postTranslate(deltaX, deltaY);
last.set(curr.x, curr.y);
}
break;
case MotionEvent.ACTION_UP:
mode = NONE;
int xDiff = (int) Math.abs(curr.x - start.x);
int yDiff = (int) Math.abs(curr.y - start.y);
if (xDiff < CLICK && yDiff < CLICK)
performClick();
break;
case MotionEvent.ACTION_POINTER_UP:
mode = NONE;
break;
}
setImageMatrix(matrix);
invalidate();
return true; // indicate event was handled
}
});
}
@Override
public void setImageBitmap(Bitmap bm) {
super.setImageBitmap(bm);
if(bm!=null)
{
bmWidth = bm.getWidth();
bmHeight = bm.getHeight();
}
}
public void setMaxZoom(float x)
{
maxScale = x;
}
private class ScaleListener extends ScaleGestureDetector.SimpleOnScaleGestureListener {
@Override
public boolean onScaleBegin(ScaleGestureDetector detector) {
mode = ZOOM;
return true;
}
@Override
public boolean onScale(ScaleGestureDetector detector) {
float mScaleFactor = (float)Math.min(Math.max(.95f, detector.getScaleFactor()), 1.05);
float origScale = saveScale;
saveScale *= mScaleFactor;
if (saveScale > maxScale) {
saveScale = maxScale;
mScaleFactor = maxScale / origScale;
} else if (saveScale < minScale) {
saveScale = minScale;
mScaleFactor = minScale / origScale;
}
right = width * saveScale - width - (2 * redundantXSpace * saveScale);
bottom = height * saveScale - height - (2 * redundantYSpace * saveScale);
if (origWidth * saveScale <= width || origHeight * saveScale <= height) {
matrix.postScale(mScaleFactor, mScaleFactor, detector.getFocusX(), detector.getFocusY());
if (mScaleFactor < 1) {
matrix.getValues(m);
float x = m[Matrix.MTRANS_X];
float y = m[Matrix.MTRANS_Y];
if (mScaleFactor < 1) {
if (Math.round(origWidth * saveScale) < width) {
if (y < -bottom)
matrix.postTranslate(0, -(y + bottom));
else if (y > 0)
matrix.postTranslate(0, -y);
} else {
if (x < -right)
matrix.postTranslate(-(x + right), 0);
else if (x > 0)
matrix.postTranslate(-x, 0);
}
}
}
} else {
matrix.postScale(mScaleFactor, mScaleFactor, detector.getFocusX(), detector.getFocusY());
matrix.getValues(m);
float x = m[Matrix.MTRANS_X];
float y = m[Matrix.MTRANS_Y];
if (mScaleFactor < 1) {
if (x < -right)
matrix.postTranslate(-(x + right), 0);
else if (x > 0)
matrix.postTranslate(-x, 0);
if (y < -bottom)
matrix.postTranslate(0, -(y + bottom));
else if (y > 0)
matrix.postTranslate(0, -y);
}
}
return true;
}
}
@Override
protected void onMeasure (int widthMeasureSpec, int heightMeasureSpec)
{
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
width = MeasureSpec.getSize(widthMeasureSpec);
height = MeasureSpec.getSize(heightMeasureSpec);
//Fit to screen.
float scale;
float scaleX = (float)width / (float)bmWidth;
float scaleY = (float)height / (float)bmHeight;
scale = Math.min(scaleX, scaleY);
matrix.setScale(scale, scale);
setImageMatrix(matrix);
saveScale = 1f;
// Center the image
redundantYSpace = (float)height - (scale * (float)bmHeight) ;
redundantXSpace = (float)width - (scale * (float)bmWidth);
redundantYSpace /= (float)2;
redundantXSpace /= (float)2;
matrix.postTranslate(redundantXSpace, redundantYSpace);
origWidth = width - 2 * redundantXSpace;
origHeight = height - 2 * redundantYSpace;
right = width * saveScale - width - (2 * redundantXSpace * saveScale);
bottom = height * saveScale - height - (2 * redundantYSpace * saveScale);
setImageMatrix(matrix);
}
}
并按下关闭按钮，我将返回上一阶段。但缩放在这里不起作用。有人能说我在这里缺少什么吗？