Android 设置 Keyguard 默认 Widget

OS: Android 4.4


``` xml
<string name="widget_default_package_name">net.lnmcc.mywidget</string>
<string name="widget_default_class_name">net.lnmcc.mywidget</string>

Android Makefile 引用第三方库

LOCAL_PATH:= $(call my-dir)

include $(CLEAR_VARS)

LOCAL_SRC_FILES := $(call all-java-files-under, src) $(call all-subdir-Iaidl-files)

LOCAL_JAVA_LIBRARIES := services telephony-common

LOCAL_STATIC_JAVA_LIBRARIES := MyLib

LOCAL_PACKAGE_NAME := Keyguard

LOCAL_CERTIFICATE := platform

LOCAL_PRIVILEGED_MODULE := true

LOCAL_PROGUARD_FLAG_FILES := proguard.flags

include $(BUILD_PACKAGE)

include $(CLEAR_VARS)

LOCAL_PREBUILT_STATIC_JAVA_LIBRARIES := MyLib:libs/mylib-v8.jar

include $(BUILD_MULTI_PREBUILT)

Android Check Long Press Helper

基本思想:在Down事件中向UI线程塞入一个定时任务,如果在定时时间终了前任务没有被取消,就认为是一个长按事件。

/*
 * Copyright (C) 2012 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.android.keyguard;

import android.view.MotionEvent;
import android.view.View;
import android.view.ViewConfiguration;

public class CheckLongPressHelper {
    private View mView;
    private boolean mHasPerformedLongPress;
    private CheckForLongPress mPendingCheckForLongPress;
    private float mDownX, mDownY;
    private int mLongPressTimeout;
    private int mScaledTouchSlop;

    class CheckForLongPress implements Runnable {
        public void run() {
            if ((mView.getParent() != null) && mView.hasWindowFocus()
                    && !mHasPerformedLongPress) {
                if (mView.performLongClick()) {
                    mView.setPressed(false);
                    mHasPerformedLongPress = true;
                }
            }
        }
    }

    public CheckLongPressHelper(View v) {
        mScaledTouchSlop = ViewConfiguration.get(v.getContext()).getScaledTouchSlop();
        mLongPressTimeout = ViewConfiguration.getLongPressTimeout();
        mView = v;
    }

    public void postCheckForLongPress(MotionEvent ev) {
        mDownX = ev.getX();
        mDownY = ev.getY();
        mHasPerformedLongPress = false;

        if (mPendingCheckForLongPress == null) {
            mPendingCheckForLongPress = new CheckForLongPress();
        }
        mView.postDelayed(mPendingCheckForLongPress, mLongPressTimeout);
    }

    public void onMove(MotionEvent ev) {
        float x = ev.getX();
        float y = ev.getY();
        boolean xMoved = Math.abs(mDownX - x) > mScaledTouchSlop;
        boolean yMoved = Math.abs(mDownY - y) > mScaledTouchSlop;

        if (xMoved || yMoved) {
            cancelLongPress();
        }
    }

    public void cancelLongPress() {
        mHasPerformedLongPress = false;
        if (mPendingCheckForLongPress != null) {
            mView.removeCallbacks(mPendingCheckForLongPress);
            mPendingCheckForLongPress = null;
        }
    }

    public boolean hasPerformedLongPress() {
        return mHasPerformedLongPress;
    }
}

ref:Android-4.4/frameworks/base/packages/Keyguard/src/com/android/keyguard/CheckLongPressHelpe

在 Android Makefile 中使用通配符

LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE    := Hello
LOCAL_SRC_FILES := $(wildcard $(LOCAL_PATH)/*.c)
include $(BUILD_STATIC_LIBRARY)

Android FragmentPagerAdapter Demo

package com.example.sijiewang.testviewpager;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.view.ViewPager;
import java.util.ArrayList;

public class MainActivity extends FragmentActivity {
    private ViewPager mAlarmCreateViewPager;
    private Fragment mFragmentOne;
    private Fragment mFragmentTwo;
    private ArrayList<Fragment> mFragmentList;

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

        mFragmentList = new ArrayList<Fragment>(2);
        mFragmentOne = new mFragmentOne();
        mFragmentList.add(mFragmentOne);
        mFragmentTwo = new mFragmentTwo();
        mFragmentList.add(mFragmentTwo);

        mAlarmCreateViewPager = (ViewPager) findViewById(R.id.viewpager);
        mAlarmCreateViewPager.setAdapter(new FragmentPagerAdapterDemo(getSupportFragmentManager()));
    }

    class FragmentPagerAdapterDemo extends FragmentPagerAdapter {

        public PagerAdapterDemo(FragmentManager fm) {
            super(fm);
        }

        @Override
        public Fragment getItem(int arg0) {
            return mFragmentList.get(arg0);
        }

        @Override
        public int getCount() {
            return mFragmentList.size();
        }

    }
}

一些特性:1.当使用FragmentPagerAdapter时,所有的Fragment都不会被销毁,但是Fragment本身生命周期中跟UI相关的方法在每次显示状态改变的时候都会被重复调用。2.由于第一条中的原因,FragmentPagerAdapter不适合大量数据的展示。当有大量数据时,GOOGLE推荐使用FragmentStatePagerAdapter。