我已经看到了很多的代码在这里这有利于缩小你textview但没有人用我的文字工作，因为它是内scrollview 。 我怎样才能摆脱这个问题的？
import android.app.Activity;
import android.os.Bundle;
import android.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;
import android.widget.TextView;
public class Introduce extends Activity implements OnTouchListener{
final static float STEP = 200;
TextView mtxtRatio1,mtxtRatio2,mtxtRatio3,mtxtRatio4;
float mRatio = 1.0f;
int mBaseDist;
float mBaseRatio;
float fontsize = 13;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.introduce);
mtxtRatio1 = (TextView)findViewById(R.id.intro1);
mtxtRatio1.setTextSize(mRatio+13);
}
public boolean onTouchEvent(MotionEvent event) {
if (event.getPointerCount() == 2) {
int action = event.getAction();
int pureaction = action & MotionEvent.ACTION_MASK;
if (pureaction == MotionEvent.ACTION_POINTER_DOWN) {
mBaseDist = getDistance(event);
mBaseRatio = mRatio;
} else {
float delta = (getDistance(event) - mBaseDist) / STEP;
float multi = (float)Math.pow(2, delta);
mRatio = Math.min(1024.0f, Math.max(0.1f, mBaseRatio * multi));
mtxtRatio1.setTextSize(mRatio+13);
}
}
return true;
}
int getDistance(MotionEvent event) {
int dx = (int)(event.getX(0) - event.getX(1));
int dy = (int)(event.getY(0) - event.getY(1));
return (int)(Math.sqrt(dx * dx + dy * dy));
}
public boolean onTouch(View v, MotionEvent event) {
// TODO Auto-generated method stub
return false;
}
}
使用Polidea的ZOOMVIEW，它工作在一个滚动视图，并具有双指缩放和双击放大，有一点想，我结束了禁用双指缩放，只是使用双击
https://github.com/Polidea/android-zoom-view
把你的TextView使用的是成住在一个ZOOMVIEW一个的LinearLayout其住在滚动型，如andany其他浏览次数：
<ScrollView
android:layout_width="match_parent"
android:layout_height="wrap_content">
<com.polidea.ZoomView
android:layout_width="match_parent"
android:layout_height="wrap_content" >
<LinearLayout
android:id="@+id/myLinearLayout"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical" >
</LinearLayout>
</com.polidea.ZoomView>
</ScrollView>
希望这会帮助别人。 这个答案是从这里和这里 。
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
tv = (TextView) findViewById(R.id.tv);
tv.setText(getString(R.string.hello_world));
scaleGestureDetector = new ScaleGestureDetector(this, new simpleOnScaleGestureListener());
tv.setOnTouchListener(new OnTouchListener() {
@Override
public boolean onTouch(View v, MotionEvent event) {
if(event.getPointerCount() == 1){
//stuff for 1 pointer
}else{ //when 2 pointers are present
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
// Disallow ScrollView to intercept touch events.
v.getParent().requestDisallowInterceptTouchEvent(true);
scaleGestureDetector.onTouchEvent(event);
break;
case MotionEvent.ACTION_MOVE:
// Disallow ScrollView to intercept touch events.
v.getParent().requestDisallowInterceptTouchEvent(true);
scaleGestureDetector.onTouchEvent(event);
break;
case MotionEvent.ACTION_UP:
// Allow ScrollView to intercept touch events.
v.getParent().requestDisallowInterceptTouchEvent(false);
break;
}
}
return true;
}
});
}
从答案这里有当即便手指静态文本被调整（屏幕上的两个手指）的问题。 我所做的是添加校验，以使textSize不进行任何更改瞬间。
private float safe;
public class simpleOnScaleGestureListener extends SimpleOnScaleGestureListener {
@Override
public boolean onScale(ScaleGestureDetector detector) {
// TODO Auto-generated method stub
float size = tv.getTextSize();
Log.d("TextSizeStart", String.valueOf(size));
//float factor = detector.getScaleFactor();
float factor = Math.max(0.5f, Math.min(detector.getScaleFactor(), 2f));
Log.d("Factor", String.valueOf(factor));
float product = size*factor;
Log.d("TextSize", String.valueOf(product));
safe = Math.abs(product - size);
if(product <= 100 && product >= 20 && safe < 3){
//tv.setText("factor= " +factor + "\n" + "product = \n" + size + " * " + factor + " \n= " + product +"\n" + getString(R.string.hello_world));
tv.setTextSize(TypedValue.COMPLEX_UNIT_PX, product);
}
size = tv.getTextSize();
Log.d("TextSizeEnd", String.valueOf(size));
return true;
}
}
你可以玩safe < 3至您所期望的价值。
以下是在TextView中与实施双指缩放的方式/无滚动型
MainActivity.java
public class MainActivity extends AppCompatActivity{
final static float STEP = 200;
float mRatio = 1.0f;
int mBaseDist;
float mBaseRatio;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setHasOptionsMenu(true);
textViewData = (TextView).findViewById(R.id.tvContributeData);
textViewData.setOnTouchListener(new View.OnTouchListener() {
@Override
public boolean onTouch(View view, MotionEvent event) {
if (event.getPointerCount() == 2) {
int action = event.getAction();
int pureaction = action & MotionEvent.ACTION_MASK;
if (pureaction == MotionEvent.ACTION_POINTER_DOWN) {
mBaseDist = getDistance(event);
mBaseRatio = mRatio;
} else {
float delta = (getDistance(event) - mBaseDist) / STEP;
float multi = (float) Math.pow(2, delta);
mRatio = Math.min(1024.0f, Math.max(0.1f, mBaseRatio * multi));
textViewData.setTextSize(mRatio + 13);
}
}
return true;
});
int getDistance(MotionEvent event) {
int dx = (int) (event.getX(0) - event.getX(1));
int dy = (int) (event.getY(0) - event.getY(1));
return (int) (Math.sqrt(dx * dx + dy * dy));
}
}
}
