网站策划是什么,程序员网站需要多少钱,做个公司网站大概多少钱,appserv做网站教程本文主要讲述了利用android自定义控件实现瀑布流与水波纹效果
首先为实现效果#xff0c;应了解touch事件在android中的传递机制 在执行touch事件时
首先执行dispatchTouchEvent方法#xff0c;执行事件分发。 再执行onInterceptTouchEvent方法#xff0c;判断是否中断事件…本文主要讲述了利用android自定义控件实现瀑布流与水波纹效果
首先为实现效果应了解touch事件在android中的传递机制 在执行touch事件时
首先执行dispatchTouchEvent方法执行事件分发。 再执行onInterceptTouchEvent方法判断是否中断事件返回true时中断执行自己的onTouchEvnet方法.最后执行onTouchEvent方法处理事件
瀑布流实现
首先定义三个listView竖起排列并且配置适配器
public class MainActivity extends Activity {private ListView lv1;private ListView lv2;private ListView lv3;Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);lv1 (ListView) findViewById(R.id.lv1);lv2 (ListView) findViewById(R.id.lv2);lv3 (ListView) findViewById(R.id.lv3);try {lv1.setAdapter(new MyAdapter1());lv2.setAdapter(new MyAdapter1());lv3.setAdapter(new MyAdapter1());} catch (Exception e) {e.printStackTrace();}}private int ids[] new int[] { R.drawable.default1, R.drawable.girl1,R.drawable.girl2, R.drawable.girl3 };class MyAdapter1 extends BaseAdapter {Overridepublic int getCount() {return 3000;}Overridepublic Object getItem(int position) {return position;}Overridepublic long getItemId(int position) {return 0;}Overridepublic View getView(int position, View convertView, ViewGroup parent) {ImageView iv (ImageView) View.inflate(getApplicationContext(),R.layout.lv_item, null);int resId (int) (Math.random() * 4);iv.setImageResource(ids[resId]);return iv;}}
}布局文件的配置
com.example.pinterestlistview.MyLinearLayout xmlns:androidhttp://schemas.android.com/apk/res/androidxmlns:toolshttp://schemas.android.com/toolsandroid:layout_widthmatch_parentandroid:layout_heightmatch_parentandroid:idid/mlltools:context.MainActivity ListViewandroid:idid/lv2android:scrollbarsnoneandroid:layout_width0dpandroid:layout_heightwrap_contentandroid:layout_weight1 /ListViewandroid:idid/lv1android:scrollbarsnoneandroid:layout_width0dpandroid:layout_heightwrap_contentandroid:layout_weight1 /ListViewandroid:idid/lv3android:scrollbarsnoneandroid:layout_width0dpandroid:layout_heightwrap_contentandroid:layout_weight1 //com.example.pinterestlistview.MyLinearLayout
自定义类截取事件分发
public class MyLinearLayout extends LinearLayout {public MyLinearLayout(Context context, AttributeSet attrs) {super(context, attrs);}Overridepublic boolean onInterceptTouchEvent(MotionEvent ev) {return true;}Overridepublic boolean dispatchTouchEvent(MotionEvent ev) {return super.dispatchTouchEvent(ev);}Overridepublic boolean onTouchEvent(MotionEvent event) {int widthgetWidth()/getChildCount();int height getHeight();int countgetChildCount();float eventX event.getX();if (eventXwidth){ // 滑动左边的 listViewevent.setLocation(width/2, event.getY());getChildAt(0).dispatchTouchEvent(event);return true;} else if (eventX width eventX 2 * width) { //滑动中间的 listView float eventY event.getY();if (eventY height / 2) {event.setLocation(width / 2, event.getY());for (int i 0; i count; i) {View child getChildAt(i);try {child.dispatchTouchEvent(event);} catch (Exception e) {e.printStackTrace();}}return true;} else if (eventY height / 2) {event.setLocation(width / 2, event.getY());try {getChildAt(1).dispatchTouchEvent(event);} catch (Exception e) {e.printStackTrace();}return true;}}else if (eventX2*width){event.setLocation(width/2, event.getY());getChildAt(2).dispatchTouchEvent(event);return true;}return true;}}
完成运行效果如下 水波纹效果实现
要实现水波纹效果只需用一个自定义控件填充整个Activity即可 com.zj.wave.MyWaveandroid:layout_widthfill_parentandroid:layout_heightfill_parent/
自定义控件实现
/*** 水波纹效果* author leo**/
public class MyRingWave extends View{/*** 二个相临波浪中心点的最小距离*/private static final int DIS_SOLP 13;protected boolean isRunning false;private ArrayListWave wList;public MyRingWave(Context context, AttributeSet attrs) {super(context, attrs);wList new ArrayListMyRingWave.Wave();}private Handler handler new Handler(){public void handleMessage(android.os.Message msg) {//刷新数据flushData();//刷新页面invalidate();//循环动画if (isRunning) {handler.sendEmptyMessageDelayed(0, 50);}};};Overrideprotected void onDraw(Canvas canvas) {for (int i 0; i wList.size(); i) {Wave wave wList.get(i);canvas.drawCircle(wave.cx, wave.cy, wave.r, wave.p);}}Overridepublic boolean onTouchEvent(MotionEvent event) {super.onTouchEvent(event);switch (event.getAction()) {case MotionEvent.ACTION_DOWN:case MotionEvent.ACTION_MOVE:int x (int) event.getX();int y (int) event.getY();addPoint(x,y);break;default:break;}return true; }/*** 添加新的波浪中心点* param x* param y*/private void addPoint(int x, int y) {if(wList.size() 0){addPoint2List(x,y);/** 第一次启动动画*/isRunning true;handler.sendEmptyMessage(0);}else{Wave w wList.get(wList.size()-1);if(Math.abs(w.cx - x)DIS_SOLP || Math.abs(w.cy-y)DIS_SOLP){addPoint2List(x,y);}};}/*** 添加新的波浪* param x* param y*/private void addPoint2List(int x, int y) {Wave w new Wave();w.cx x;w.cyy;Paint panew Paint();pa.setColor(colors[(int)(Math.random()*4)]);pa.setAntiAlias(true);pa.setStyle(Style.STROKE);w.p pa;wList.add(w);}private int [] colors new int[]{Color.BLUE,Color.RED,Color.YELLOW,Color.GREEN};/*** 刷新数据*/private void flushData() {for (int i 0; i wList.size(); i) {Wave w wList.get(i);//如果透明度为 0 从集合中删除int alpha w.p.getAlpha();if(alpha 0){wList.remove(i); //删除i 以后i的值应该再减1 否则会漏掉一个对象不过在此处影响不大效果上看不出来。continue;}alpha-5;if(alpha5){alpha 0;}//降低透明度w.p.setAlpha(alpha);//扩大半径w.r w.r3;//设置半径厚度w.p.setStrokeWidth(w.r/3);}/** 如果集合被清空就停止刷新动画*/if(wList.size() 0){isRunning false;}}/*** 定义一个波浪* author leo*/private class Wave {//圆心int cx;int cy;//画笔Paint p;//半径int r;}
}
完成效果如下
