1. 程式人生 > >抽屜式選單-仿QQ5.0側滑選單

抽屜式選單-仿QQ5.0側滑選單

為擴充套件螢幕尺寸所帶來的侷限性,很多APP都有側滑選單。所謂的側滑選單就是將一些選單選項隱藏起來,而不是放置在主螢幕上,然後可以通過滑動的方式將選單顯示出來。

本文將通過android提供的HorizontalScrollView來實現一個仿QQ5.0側滑選單的案例,通過自定義控制元件和屬性動畫來實現側滑效果。

1. 最終效果圖


2. 佈局檔案

left_menu.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >
    
    <Button 
        android:id="@+id/call"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="160dp"
        android:drawableLeft="@drawable/nav_call"
        android:drawablePadding="20dp"
        android:paddingLeft="20dp"
        android:text="Call"
        android:gravity="center_vertical"
        android:background="@null"/>
    
    <Button 
        android:id="@+id/friends"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:drawableLeft="@drawable/nav_friends"
        android:drawablePadding="20dp"
        android:text="Friends"
        android:gravity="center_vertical"
        android:paddingLeft="20dp"
        android:background="@null"/>

    <Button 
        android:id="@+id/location"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:drawableLeft="@drawable/nav_location"
        android:drawablePadding="20dp"
        android:text="Location"
        android:gravity="center_vertical"
        android:paddingLeft="20dp"
        android:background="@null"/>
    
    <Button 
        android:id="@+id/mail"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:drawableLeft="@drawable/nav_mail"
        android:drawablePadding="20dp"
        android:text="Mail"
        android:gravity="center_vertical"
        android:paddingLeft="20dp"
        android:background="@null"/>
    
    <Button 
        android:id="@+id/tasks"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:drawableLeft="@drawable/nav_task"
        android:drawablePadding="20dp"
        android:text="Tasks"
        android:gravity="center_vertical"
        android:paddingLeft="20dp"
        android:background="@null"/>

</LinearLayout>
activity_main.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    xmlns:yxman="http://schemas.android.com/apk/res/com.yx.slidingmenu"
    android:layout_width="match_parent"
    android:layout_height="match_parent" >

    <com.yx.slidingmenu.view.SlidingMenu
        android:id="@+id/id_menu"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:background="@drawable/sliding_menu_background"
        yxman:rightPadding="80dp" >

        <LinearLayout
            android:layout_width="wrap_content"
            android:layout_height="match_parent"
            android:orientation="horizontal" >

            <include layout="@layout/left_menu" />

            <LinearLayout
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:background="@drawable/home_background_image"
                android:orientation="vertical" >

                <RelativeLayout
                    android:layout_width="match_parent"
                    android:layout_height="50dp"
                    android:background="#13b7f6" >

                    <Button
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:background="@drawable/ic_menu"
                        android:onClick="toggleMenu" />
                </RelativeLayout>
            </LinearLayout>
        </LinearLayout>
    </com.yx.slidingmenu.view.SlidingMenu>

</RelativeLayout>

首先自定義一個用於顯示側滑選單的left_menu.xml佈局檔案,然後在activity_main.xml主佈局檔案中通過一個水平的LinearLayout將子佈局檔案載入進來,以及將主佈局檔案編寫在其中。

3. 新增自定義屬性

a. 首先在values下新建attr.xml,程式碼如下:

<?xml version="1.0" encoding="utf-8"?>
<resources>

    <attr name="rightPadding" format="dimension"></attr>

    <declare-styleable name="SlidingMenu">
        <attr name="rightPadding"></attr>
    </declare-styleable>

</resources>
b. 在主佈局activity_main.xml中宣告名稱空間和使用自定的屬性:
<com.yx.slidingmenu.view.SlidingMenu
        android:id="@+id/id_menu"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:background="@drawable/sliding_menu_background"
        yxman:rightPadding="80dp" >
        ......
</com.yx.slidingmenu.view.SlidingMenu>

我的名稱空間是xmlns:yxman="http://schemas.android.com/apk/res/com.yx.slidingmenu"。格式是:http://schemas.android.com/apk/res/後面再加上專案的包名。

屬性yxman:rightPadding="80dp"右側內邊距設定為80dp。

4. 自定義SlidingMenu

SlidingMenu.java

package com.yx.slidingmenu.view;

import com.nineoldandroids.view.ViewHelper;
import com.yx.slidingmenu.R;
import android.content.Context;
import android.content.res.TypedArray;
import android.util.AttributeSet;
import android.util.DisplayMetrics;
import android.util.TypedValue;
import android.view.MotionEvent;
import android.view.ViewGroup;
import android.view.WindowManager;
import android.widget.HorizontalScrollView;
import android.widget.LinearLayout;

public class SlidingMenu extends HorizontalScrollView {

	private LinearLayout mWapper;
	private ViewGroup mMenu;
	private ViewGroup mContent;
	private int mScreenWidth;
	private int mMenuWidth;

	// 單位是dp
	private int mMenuRightPadding = 50;

	private boolean flag;
	private boolean isOpen;

	public SlidingMenu(Context context) {
		this(context, null);
	}

	/**
	 * 未使用自定義屬性時呼叫
	 * 
	 * @param context
	 * @param attrs
	 */
	public SlidingMenu(Context context, AttributeSet attrs) {
		this(context, attrs, 0);
	}

	/**
	 * 當使用了自定義屬性時會呼叫此構造方法
	 * 
	 * @param context
	 * @param attrs
	 * @param defStyle
	 */
	public SlidingMenu(Context context, AttributeSet attrs, int defStyle) {
		super(context, attrs, defStyle);

		// 獲取自定義定義的屬性
		TypedArray attribute = context.getTheme().obtainStyledAttributes(attrs, R.styleable.SlidingMenu, defStyle, 0);

		int n =  attribute.getIndexCount();
		for (int i = 0; i < n; i++) {
			int attr = attribute.getIndex(i);

			switch (attr) {
			case R.styleable.SlidingMenu_rightPadding:
				int defValue = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 50, context.getResources().getDisplayMetrics());
				mMenuRightPadding = attribute.getDimensionPixelSize(attr, defValue);
				break;
			}
		}
		attribute.recycle();

		WindowManager wm = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
		DisplayMetrics outMetrics = new DisplayMetrics();
		wm.getDefaultDisplay().getMetrics(outMetrics);
		mScreenWidth = outMetrics.widthPixels;
	}

	/**
	 * 設定子View的寬和高,設定自己的寬和高
	 */
	@Override
	protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
		if (!flag) {
			mWapper = (LinearLayout) getChildAt(0);
			mMenu = (ViewGroup) mWapper.getChildAt(0);
			mContent = (ViewGroup) mWapper.getChildAt(1);
			mMenuWidth = mMenu.getLayoutParams().width = mScreenWidth - mMenuRightPadding;
			mContent.getLayoutParams().width = mScreenWidth;
			flag = true;
		}
		super.onMeasure(widthMeasureSpec, heightMeasureSpec);
	}

	/**
	 * 通過設定偏移量,將menu隱藏
	 */
	@Override
	protected void onLayout(boolean changed, int l, int t, int r, int b) {
		super.onLayout(changed, l, t, r, b);
		if (changed) {
			this.scrollTo(mMenuWidth, 0);
		}
	}

	@Override
	public boolean onTouchEvent(MotionEvent ev) {
		int action = ev.getAction();
		switch (action) {
		case MotionEvent.ACTION_UP:
			// 隱藏在左邊的寬度
			int scrollX = getScrollX();
			if (scrollX >= mMenuWidth / 2) {
				this.smoothScrollTo(mMenuWidth, 0);
				isOpen = false;
			} else {
				this.smoothScrollTo(0, 0);
				isOpen = true;
			}
			return true;
		}
		return super.onTouchEvent(ev);
	}

	/**
	 * 切換選單
	 */
	public void toggle() {
		if (isOpen) {
			closeMenu();
		} else {
			openMenu();
		}
	}

	/**
	 * 開啟選單
	 */
	public void openMenu() {
		if (isOpen)
			return;
		this.smoothScrollTo(0, 0);
		isOpen = true;
	}

	/**
	 * 關閉選單
	 */
	public void closeMenu() {
		if (!isOpen)
			return;
		this.smoothScrollTo(mMenuWidth, 0);
		isOpen = false;
	}

	/**
	 * 滾動發生時
	 */
	@Override
	protected void onScrollChanged(int l, int t, int oldl, int oldt) {
		super.onScrollChanged(l, t, oldl, oldt);
		
		// scale取值範圍:0~1
		float scale = l * 1.0f / mMenuWidth; 

		/**
		 * 1. 內容區域0.7~1.0 縮放的效果 scale: (0.7 + 0.3 * scale)
		 * 2. 選單的偏移量需要修改
		 * 3. 選單的顯示時有縮放以及透明度變化:
		 *      縮放: 0.7 ~1.0 -> 1.0 - scale * 0.3 
		 *      透明度: 0.6 ~ 1.0 -> 1.0 - scale * 0.4
		 */
		float rightScale = 0.7f + 0.3f * scale;
		float leftScale = 1.0f - scale * 0.3f;
		float leftAlpha = 1.0f - scale * 0.4f;

		// 呼叫屬性動畫,設定TranslationX
		ViewHelper.setTranslationX(mMenu, mMenuWidth * scale * 0.8f);
		ViewHelper.setScaleX(mMenu, leftScale);
		ViewHelper.setScaleY(mMenu, leftScale);
		ViewHelper.setAlpha(mMenu, leftAlpha);
		// 設定content的縮放的中心點
		ViewHelper.setPivotX(mContent, 0);
		ViewHelper.setPivotY(mContent, mContent.getHeight() / 2);
		ViewHelper.setScaleX(mContent, rightScale);
		ViewHelper.setScaleY(mContent, rightScale);
	}
}

以上程式碼看著很複雜,但都有詳細的註釋,主要是用於處理滑動事件,不過多解釋。

5. MainActivity.java

package com.yx.slidingmenu;

import com.yx.slidingmenu.view.SlidingMenu;
import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;

public class MainActivity extends Activity {

	private SlidingMenu mLeftMenu;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);

		mLeftMenu = (SlidingMenu) findViewById(R.id.id_menu);
	}

	public void toggleMenu(View view) {
		mLeftMenu.toggle();
	}

	@Override
	public boolean onCreateOptionsMenu(Menu menu) {
		getMenuInflater().inflate(R.menu.main, menu);
		return true;
	}
}

至此,核心程式碼和主要演示過程以完畢。是不是感覺很炫酷,就是這麼簡單。如有疑問下載原始碼自行研究。