作者:驰诗勋 | 来源:互联网 | 2023-09-02 16:17
之前做项目要对图片的查看,然后就自己写了一个,适合对图片的浏览,跟系统图库的效果一样哦,先贴一张美女图片,听说有美女,男人就会多看一眼,不知道是不是真的,哈哈布局文件需要注意的一点
之前做项目要对图片的查看,然后就自己写了一个,适合对图片的浏览,跟系统图库的效果一样哦,先贴一张美女图片,听说有美女,男人就会多看一眼,不知道是不是真的,哈哈
布局文件需要注意的一点是 scaleType一定要是 matrix,这样才能对图片进行一系列的矩阵操作,例如放大缩小,拖拽,等等
- <RelativeLayout 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" >
-
- <ImageView
- android:id="@+id/imageView1"
- android:layout_width="fill_parent"
- android:layout_height="fill_parent"
- android:scaleType="matrix" />
-
- RelativeLayout>
代码我都有注释,直接上代码咯
- package com.example.zoomanddrafting;
-
- import android.app.Activity;
- import android.content.Context;
- import android.content.Intent;
- import android.graphics.Bitmap;
- import android.graphics.BitmapFactory;
- import android.graphics.Matrix;
- import android.graphics.PointF;
- import android.graphics.RectF;
- import android.os.Bundle;
- import android.util.DisplayMetrics;
- import android.util.FloatMath;
- import android.view.MotionEvent;
- import android.view.View;
- import android.view.View.OnTouchListener;
- import android.widget.ImageView;
-
-
-
- public class PhotoViewer extends Activity implements OnTouchListener {
-
- private static final String TAG = "PhotoViewer";
- public static final int RESULT_CODE_NOFOUND = 200;
-
-
- Matrix matrix = new Matrix();
- Matrix savedMatrix = new Matrix();
- DisplayMetrics dm;
- ImageView imgView;
- Bitmap bitmap;
-
-
- float minScaleR = 1.0f;
-
- static final float MAX_SCALE = 10f;
-
-
- static final int NONE = 0;
-
- static final int DRAG = 1;
-
- static final int ZOOM = 2;
-
-
- int mode = NONE;
-
- PointF prev = new PointF();
- PointF mid = new PointF();
- float dist = 1f;
-
-
- @Override
- public void onCreate(Bundle savedInstanceState) {
- super.onCreate(savedInstanceState);
-
- bitmap = BitmapFactory.decodeResource(getResources(), R.drawable.item);
-
- setContentView(R.layout.activity_main);
- imgView = (ImageView) findViewById(R.id.imageView1);
- imgView.setImageBitmap(bitmap);
- imgView.setOnTouchListener(this);
- dm = new DisplayMetrics();
- getWindowManager().getDefaultDisplay().getMetrics(dm);
-
- center();
- imgView.setImageMatrix(matrix);
-
- }
-
- public void SureOnClick(View v)
- {
-
- }
-
-
-
-
- public boolean onTouch(View v, MotionEvent event) {
-
- switch (event.getAction() & MotionEvent.ACTION_MASK) {
-
- case MotionEvent.ACTION_DOWN:
- savedMatrix.set(matrix);
- prev.set(event.getX(), event.getY());
- mode = DRAG;
- break;
-
- case MotionEvent.ACTION_POINTER_DOWN:
- dist = spacing(event);
-
- if (spacing(event) > 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() - prev.x, event.getY()
- - prev.y);
- } else if (mode == ZOOM) {
- float newDist = spacing(event);
- if (newDist > 10f) {
- matrix.set(savedMatrix);
- float tScale = newDist / dist;
- matrix.postScale(tScale, tScale, mid.x, mid.y);
- }
- }
- break;
- }
- imgView.setImageMatrix(matrix);
- CheckView();
- return true;
- }
-
-
-
-
- private void CheckView() {
- float p[] = new float[9];
- matrix.getValues(p);
- if (mode == ZOOM) {
- if (p[0] < minScaleR) {
-
- matrix.setScale(minScaleR, minScaleR);
- }
- if (p[0] > MAX_SCALE) {
-
- matrix.set(savedMatrix);
- }
- }
- center();
- }
-
-
-
-
- private void minZoom() {
- minScaleR = Math.min(
- (float) dm.widthPixels / (float) bitmap.getWidth(),
- (float) dm.heightPixels / (float) bitmap.getHeight());
- if (minScaleR < 1.0) {
- matrix.postScale(minScaleR, minScaleR);
- }
- }
-
- private void center() {
- center(true, true);
- }
-
-
-
-
- protected void center(boolean horizontal, boolean vertical) {
-
- Matrix m = new Matrix();
- m.set(matrix);
- RectF rect = new RectF(0, 0, bitmap.getWidth(), bitmap.getHeight());
- m.mapRect(rect);
-
- float height = rect.height();
- float width = rect.width();
-
- float deltaX = 0, deltaY = 0;
-
- if (vertical) {
-
- int screenHeight = dm.heightPixels;
- if (height < screenHeight) {
- deltaY = (screenHeight - height) / 2 - rect.top;
- } else if (rect.top > 0) {
- deltaY = -rect.top;
- } else if (rect.bottom < screenHeight) {
- deltaY = imgView.getHeight() - rect.bottom;
- }
- }
-
- if (horizontal) {
- int screenWidth = dm.widthPixels;
- if (width < screenWidth) {
- deltaX = (screenWidth - width) / 2 - rect.left;
- } else if (rect.left > 0) {
- deltaX = -rect.left;
- } else if (rect.right < screenWidth) {
- deltaX = screenWidth - rect.right;
- }
- }
- matrix.postTranslate(deltaX, deltaY);
- }
-
-
-
-
- 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);
- }
-
-
-
-
- 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);
- }
-
-
- }
我也将工程上传了,不要积分哦,欢迎下载
代码下载