android开发教程之实现滑动关闭fragment示例

主要代码:(有注释)

package com.example.checkboxtest;

import android.annotation.suppresslint;
import android.content.context;
import android.graphics.canvas;
import android.graphics.color;
import android.os.handler;
import android.os.message;
import android.util.attributeset;
import android.view.motionevent;
import android.view.view;
import android.view.viewgroup;
import android.widget.toast;

public class myview extends viewgroup {
    view leftview = null;
    view rightview = null;

    public myview(context context, attributeset attrs) {
        super(context, attrs);
        view view = new view(context, attrs);
        view.setbackgroundcolor(color.black);
        this.addview(view, 0);
    }

    /**
     * 测量
     */
    @suppresslint("drawallocation")
    @override
    protected void onmeasure(int widthmeasurespec, int heightmeasurespec) {
        if (getchildcount() != 2) {
            try {
                // 自定义exception
                throw new exception() {
                    @override
                    public void printstacktrace() {
                        system.err.println("myview中只能存在一个view");
                        super.printstacktrace();
                    }

                };
            } catch (exception e) {
                e.printstacktrace();
            }
        }
        leftview = getchildat(0);
        // 设置leftview的高和宽
        leftview.measure(widthmeasurespec, heightmeasurespec);
        rightview = getchildat(1);
        // 设置rightview的高和宽
        rightview.measure(widthmeasurespec, heightmeasurespec);
        super.onmeasure(widthmeasurespec, heightmeasurespec);
    }

    /**
     * 布局
     */
    @suppresslint("newapi")
    @override
    protected void onlayout(boolean changed, int l, int t, int r, int b) {
        system.out.println(l + "," + t + "," + r + "," + b);
        if (leftview != null & rightview != null) {
            // 设置leftview的位置,在屏幕右侧(初始不可见)
            leftview.layout(-r, 0, 0, b);
            // 设置rightview的位置,在屏幕中
            rightview.layout(l, t, r, b);
        }
    }

    @override
    protected void ondraw(canvas canvas) {
        super.ondraw(canvas);

    }

    @suppresslint("newapi")
    @override
    public boolean ontouchevent(motionevent event) {
        final float x = event.getx();
        float y = event.gety();
        switch (event.getaction()) {

        case motionevent.action_move:
            system.out.println("x:" + x);
            if (x < 100) {
                scrollto(0, 0);
            } else if (x > rightview.getmeasuredwidth() - 100) {// 当用户滑动至离右边缘100时,页面关闭
                new thread(new runnable() {// 新建线程,滑动关闭
                            @override
                            public void run() {
                                for (int i = 0;; i++) {
                                    try {
                                        thread.sleep(10);// rightview每隔10ms右移3,保证滑动流畅
                                    } catch (interruptedexception e) {
                                        e.printstacktrace();
                                    }
                                    int len = (int) (x + 3 * i);
                                    // system.out.println("len:" + len);
                                    message message = new message();// android中非ui线程不允许直接操作控件,可以将消息发送至主线程的handler类
                                    if (len >= rightview.getmeasuredwidth()) {
                                        message.what = 1;
                                        handler.sendmessage(message);// 发送消息
                                                                        // 关闭view
                                        break;
                                    } else {
                                        message.what = 0; // 发送消息 自动滑动
                                        handler.sendmessage(message);
                                    }
                                }
                            }
                        }).start();
            } else {
                scrollto((int) -x, 0);
                // 计算透明度信息
                float alpha = (float) (1.0 - (float) (1.0 / 400) * x);
                // system.out.println("alpha:" + al);
                // 设置透明度
                leftview.setalpha(alpha);
            }
            break;
        }
        // 设置true,消费event事件,不在向外传递
        return true;
    }

    @suppresslint("handlerleak")
    handler handler = new handler() {
        @suppresslint("newapi")
        @override
        public void handlemessage(message msg) {
            if (msg.what == 0) {
                scrollby(-3, 0);// viewgroup向右滑动3
            } else if (msg.what == 1) {
                toast.maketext(getcontext(), "关闭", 50).show();
                setvisibility(view.gone);// 设置viewgroup不可见(隐藏)
            }
        }

    };
}

使用:

<com.example.checkboxtest.myview
        android:layout_width="fill_parent"
        android:layout_height="fill_parent" >

        <view
            android:id="@+id/rightview"
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            android:background="#ff0000" />
    </com.example.checkboxtest.myview>

要显示底下的activity界面需要使用fragment的add方法

//新建一个fragment
fragment bfragment = new bfragment();
getfragmentmanager().begintransaction().add(r.id.fragment, bfragment).commit();