我是android的新手。我正在做一个包含两个垂直线性布局的项目，左线性和右线性。线性包含图像。应该将图像拖动到右线性，它们应该被缩放并移动到屏幕上的任何位置用户希望一个接一个。并且对于缩放，可以使用整个屏幕（同样对于所有图像，因此在缩放第二图像时，它甚至可以在第一图像上出现，并且我应该将组合图像一个在另一个上用于显示） .finally rightlinear应显示所有缩放和拖动的图像。请帮助我。我的主要活动是
package com.example.example;
import java.io.File;
import java.io.FileOutputStream;
import java.util.Random;
import android.graphics.Bitmap.CompressFormat;
import android.util.Log;
import android.view.DragEvent;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.DragShadowBuilder;
import android.view.View.OnClickListener;
import android.view.View.OnDragListener;
import android.view.View.OnTouchListener;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.RelativeLayout;
public class MainActivity extends Activity implements OnTouchListener,OnDragListener{
ImageView iv1,iv2,iv3,iv4,iv5,iv6,iv7,iv8;
Button display,save;
LinearLayout leftlinear;
LinearLayout rightlinear;
private static final String LOGCAT = null;
ImageView image;
AlertDialog option;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
iv1=(ImageView)findViewById(R.id.imageView1);
iv2=(ImageView)findViewById(R.id.imageView2);
iv3=(ImageView)findViewById(R.id.imageView3);
iv4=(ImageView)findViewById(R.id.imageView4);
iv5=(ImageView)findViewById(R.id.imageView5);
iv6=(ImageView)findViewById(R.id.imageView6);
iv7=(ImageView)findViewById(R.id.imageView7);
display=(Button)findViewById(R.id.button1);
save=(Button)findViewById(R.id.button2);
leftlinear=(LinearLayout)findViewById(R.id.leftlinear);
rightlinear=(LinearLayout)findViewById(R.id.rightlinear);
iv1.setDrawingCacheEnabled(true);
iv2.setDrawingCacheEnabled(true);
iv3.setDrawingCacheEnabled(true);
iv4.setDrawingCacheEnabled(true);
iv5.setDrawingCacheEnabled(true);
iv6.setDrawingCacheEnabled(true);
iv7.setDrawingCacheEnabled(true);
iv1.setOnTouchListener(this);
iv1.setDrawingCacheEnabled(true);
iv2.setOnTouchListener(this);
iv2.setDrawingCacheEnabled(true);
iv3.setOnTouchListener(this);
iv3.setDrawingCacheEnabled(true);
iv4.setOnTouchListener(this);
iv4.setDrawingCacheEnabled(true);
iv5.setOnTouchListener(this);
iv5.setDrawingCacheEnabled(true);
iv6.setOnTouchListener(this);
iv6.setDrawingCacheEnabled(true);
iv7.setOnTouchListener(this);
iv7.setDrawingCacheEnabled(true);
leftlinear.setOnDragListener(this);
rightlinear.setOnDragListener(this);
iv1.setDrawingCacheEnabled(true);
display.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
iv1.setVisibility(0);
iv2.setVisibility(0);
iv3.setVisibility(0);
iv4.setVisibility(0);
iv5.setVisibility(0);
iv6.setVisibility(0);
iv7.setVisibility(0);
}
});
save.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
rightlinear.setDrawingCacheEnabled(true);
rightlinear.buildDrawingCache();
Bitmap bitmap = rightlinear.getDrawingCache();
File resultingfile;
try {
File rootFile=new File(Environment.getExternalStorageDirectory().toString()+"/MYBOARD");
rootFile.mkdirs();
Random generator = new Random();
int n = 10000;
n = generator.nextInt(n);
String fname = "Image-"+ n +".png";
resultingfile=new File(rootFile, fname);
if (resultingfile.exists ()) resultingfile.delete ();
try {
FileOutputStream Fout = new FileOutputStream(resultingfile);
bitmap.compress(CompressFormat.PNG, 100, Fout);
Fout.flush();
Fout.close();
} catch (Exception e) {
e.printStackTrace();
}
} catch (Exception e) {
}
}
});
}
public boolean onTouch(View view, MotionEvent motionEvent) {
if (motionEvent.getAction() == MotionEvent.ACTION_DOWN) {
DragShadowBuilder shadowBuilder = new View.DragShadowBuilder(view);
view.startDrag(null, shadowBuilder, view, 0);
return true;
}
else {
return false;
}
}
public boolean onDrag(View layoutview, DragEvent dragevent) {
int action = dragevent.getAction();
switch (action) {
case DragEvent.ACTION_DRAG_STARTED:
Log.d(LOGCAT, "Drag event started");
break;
case DragEvent.ACTION_DRAG_ENTERED:
Log.d(LOGCAT, "Drag event entered into "+layoutview.toString());
break;
case DragEvent.ACTION_DRAG_EXITED:
Log.d(LOGCAT, "Drag event exited from "+layoutview.toString());
break;
case DragEvent.ACTION_DROP:
Log.d(LOGCAT, "Dropped");
image=new ImageView(this);
View view = (View) dragevent.getLocalState();
image.setImageBitmap(view.getDrawingCache());
LinearLayout container = (LinearLayout) layoutview;
container.addView(image);
image.setVisibility(View.VISIBLE);
image.setAdjustViewBounds(true);
LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.MATCH_PARENT);
image.setLayoutParams(params);
image.setScaleType(ImageView.ScaleType.MATRIX );
image.setOnTouchListener(new myTouchListener());
break;
case DragEvent.ACTION_DRAG_ENDED:
Log.d(LOGCAT, "Drag ended");
break;
default:
break;
}
return true;
}
}
and myTouchListener class is(I copied it from the net and made necessary changes)
package com.example.example;
import android.graphics.Matrix;
import android.graphics.PointF;
import android.util.FloatMath;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;
import android.view.ViewGroup.LayoutParams;
import android.widget.ImageView;
import android.widget.LinearLayout;
public class myTouchListener implements OnTouchListener {
private static final String TAG = "Touch" ;
// These matrices will be used to move and zoom image
//These matrices will be used to move and zoom image
Matrix matrix = new Matrix();
Matrix savedMatrix = 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 start = new PointF();
PointF mid = new PointF();
float oldDist = 1f;
@Override
public boolean onTouch(View v, MotionEvent event) {
// TODO Auto-generated method stub
ImageView view = (ImageView) v;
// Dump touch event to log
dumpEvent(event);
// Handle touch events here...
switch (event.getAction() & MotionEvent.ACTION_MASK) {
case MotionEvent.ACTION_DOWN:
savedMatrix.set(matrix);
start.set(event.getX(), event.getY());
mode = DRAG;
break;
case MotionEvent.ACTION_POINTER_DOWN:
oldDist = spacing(event);
if (oldDist > 10f) {
savedMatrix.set(matrix);
midPoint(mid, event);
mode = ZOOM;
}
break;
case MotionEvent.ACTION_UP:
case MotionEvent.ACTION_POINTER_UP:
mode = NONE;
break;
case MotionEvent.ACTION_MOVE:
if (mode == DRAG) {
// ...
matrix.set(savedMatrix);
matrix.postTranslate(event.getX() - start.x, event.getY() - start.y);
} else if (mode == ZOOM) {
float newDist = spacing(event);
if (newDist > 10f) {
matrix.set(savedMatrix);
float scale = newDist / oldDist;
matrix.postScale(scale, scale, mid.x, mid.y);
}
}
break;
}
view.setImageMatrix(matrix);
return true;
// indicate event was handled
}
/** Show an event in the LogCat view, for debugging */
private void dumpEvent(MotionEvent event) {
String names[] = { "DOWN", "UP", "MOVE", "CANCEL", "OUTSIDE",
"POINTER_DOWN", "POINTER_UP", "7?", "8?", "9?" };
StringBuilder sb = new StringBuilder();
int action = event.getAction();
int actionCode = action & MotionEvent.ACTION_MASK;
sb.append("event ACTION_").append(names[actionCode]);
if (actionCode == MotionEvent.ACTION_POINTER_DOWN
|| actionCode == MotionEvent.ACTION_POINTER_UP) {
sb.append("(pid ").append(
action >> MotionEvent.ACTION_POINTER_ID_SHIFT);
sb.append(")");
}
sb.append("[");
for (int i = 0; i < event.getPointerCount(); i++) {
sb.append("#").append(i);
sb.append("(pid ").append(event.getPointerId(i));
sb.append(")=").append((int) event.getX(i));
sb.append(",").append((int) event.getY(i));
if (i + 1 < event.getPointerCount())
sb.append(";");
}
sb.append("]");
}
/** Determine the space between the first two fingers */
private float spacing(MotionEvent event) {
float x = event.getX(0) - event.getX(1);
float y = event.getY(0) - event.getY(1);
return FloatMath.sqrt(x * x + y * y);
}
/** Calculate the mid point of the first two fingers */
private void midPoint(PointF point, MotionEvent event) {
float x = event.getX(0) + event.getX(1);
float y = event.getY(0) + event.getY(1);
point.set(x / 2, y / 2);
}
}
我的xml文件是
<RelativeLayout xmlns:tools="http://schemas.android.com/tools"
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/center"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity" >
<Button
android:id="@+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:layout_marginLeft="14dp"
android:text="Display" />
<Button
android:id="@+id/button2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_alignParentTop="true"
android:layout_marginRight="16dp"
android:text="Save" />
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal"
android:paddingTop="50dp"
>
<LinearLayout
android:id="@+id/leftlinear"
android:layout_width="wrap_content"
android:layout_height="fill_parent"
android:orientation="vertical" >
<ImageView
android:id="@+id/imageView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="@drawable/new1"
android:visibility="invisible" />
<ImageView
android:id="@+id/imageView2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="@drawable/new2"
android:visibility="invisible" />
<ImageView
android:id="@+id/imageView3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="@drawable/new3"
android:visibility="invisible" />
<ImageView
android:id="@+id/imageView4"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="@drawable/new4"
android:visibility="invisible" />
<ImageView
android:id="@+id/imageView5"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="@drawable/image5"
android:visibility="invisible" />
<ImageView
android:id="@+id/imageView6"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="@drawable/image6"
android:visibility="invisible" />
<ImageView
android:id="@+id/imageView7"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="@drawable/ic_launcher"
android:visibility="invisible" />
</LinearLayout>
<LinearLayout
android:id="@+id/rightlinear"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:gravity="center">
</LinearLayout>
</LinearLayout>
</RelativeLayout>