android之Widget开发详解实例三

大家好，又见面了，我是全栈君。

之前已经有过两篇写Widget的了,实例一和实例二,如果乍看这篇有难度,可以先看看前两个比较简单的.

本篇完成项目是一个小的心情记录器

整体效果图如下:

这里我们是通过点击桌面的widget弹出记录心情的activity的,

实现方法如下:

Intent intentClick = new Intent(context, update.class);
        PendingIntent pendingIntent = PendingIntent.getActivity(context, 0,
                intentClick, 0);
        rv.setOnClickPendingIntent(R.id.layout, pendingIntent);

下面是通过点击打开 Activity 操作界面的效果图

如何通过点击保存的与app Widget 做动态交互呢？来看下面这段代码

RemoteViews views = new RemoteViews(update.this
                        .getPackageName(), R.layout.main);
                views.setTextViewText(R.id.TextView01, text);
                views.setImageViewResource(R.id.ImageView01, util.image[index]);
                ComponentName widget = new ComponentName(update.this,
                        widgetProvider.class);
                AppWidgetManager manager = AppWidgetManager
                        .getInstance(update.this);
                manager.updateAppWidget(widget, views);

这里同样还是用到发RemoteViews 来接收值的变化，然后通过AppWidgetManager 这个桌面组件管理器去改新RemoteViews 。由于我们要时时刻保存用户记录的数据，这里只是用到了键值对保存。前两篇已经讲得知识点差不多了,所以这里就不仔细讲解知识点了,下面贴上代码:

package com.terry;

import android.app.Activity;
import android.appwidget.AppWidgetManager;
import android.content.ComponentName;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.RemoteViews;
import android.widget.Spinner;
import android.widget.AdapterView.OnItemSelectedListener;

public class update extends Activity {

    private EditText mEditText;
    private Button mButton;

    private Spinner mSpinner;

    private int index = 0;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        setContentView(R.layout.update);

        mEditText = (EditText) findViewById(R.id.EditText01);
        mButton = (Button) findViewById(R.id.Button01);
        mSpinner = (Spinner) findViewById(R.id.Spinner01);
        final ImageView iv = (ImageView) findViewById(R.id.ImageView01);
        ArrayAdapter<String> adpter = new ArrayAdapter<String>(this,
                android.R.layout.simple_spinner_dropdown_item, util.text);
        adpter
                .setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
        mSpinner.setAdapter(adpter);

        SharedPreferences settings = getSharedPreferences("settinginfo",
                Activity.MODE_PRIVATE);
        index = settings.getInt("imageState", 0);
        mEditText.setText(settings.getString("heart", ""));
        iv.setImageResource(util.image[index]);
        mSpinner.setSelection(index);
        mSpinner.setOnItemSelectedListener(new OnItemSelectedListener() {

            @Override
            public void onItemSelected(AdapterView arg0, View arg1,
                    int arg2, long arg3) {
                // TODO Auto-generated method stub
                index = arg2;

                iv.setImageResource(util.image[index]);

            }

            @Override
            public void onNothingSelected(AdapterView arg0) {
                // TODO Auto-generated method stub

            }
        });
        mButton.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                String text = mEditText.getText().toString();
                if (text.equals("")) {
                    return;
                }
                SharedPreferences shared = getSharedPreferences("settinginfo",
                        Activity.MODE_PRIVATE);
                SharedPreferences.Editor editor = shared.edit();
                editor.putInt("imageState", index);
                editor.putString("heart", text);
                editor.commit();
                RemoteViews views = new RemoteViews(update.this
                        .getPackageName(), R.layout.main);
                views.setTextViewText(R.id.TextView01, text);
                views.setImageViewResource(R.id.ImageView01, util.image[index]);
                ComponentName widget = new ComponentName(update.this,
                        widgetProvider.class);
                AppWidgetManager manager = AppWidgetManager
                        .getInstance(update.this);
                manager.updateAppWidget(widget, views);
                update.this.finish();

            }
        });

    }
}

由于组件每创建一次都调用了一次updateAppWidget 这个方法，故此方法也必须去获取键值对

package com.terry;

import android.app.Activity;
import android.app.PendingIntent;
import android.appwidget.AppWidgetManager;
import android.appwidget.AppWidgetProvider;
import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.widget.RemoteViews;
import android.widget.Toast;

public class widgetProvider extends AppWidgetProvider {

    private static RemoteViews rv;

    @Override
    public void onUpdate(Context context, AppWidgetManager appWidgetManager,
            int[] appWidgetIds) {
        // TODO Auto-generated method stub
        final int N = appWidgetIds.length;
        for (int i = 0; i < N; i++) {
            int appWidgetId = appWidgetIds[i];
            updateAppWidget(context, appWidgetManager, appWidgetId);
        }
    }

    @Override
    public void onReceive(Context context, Intent intent) {
        // TODO Auto-generated method stub
        super.onReceive(context, intent);

        
        
    }

    public static void updateAppWidget(Context context,
            AppWidgetManager appWidgeManger, int appWidgetId) {
        rv = new RemoteViews(context.getPackageName(), R.layout.main);

        SharedPreferences shared = context.getSharedPreferences("settinginfo",
                Activity.MODE_PRIVATE);
        // util.index = settings.getInt("imageState", 0);
        // mEditText.setText(settings.getString("heart", ""));
        rv.setTextViewText(R.id.TextView01, shared.getString("heart", context
                .getResources().getString(R.string.load)));
        rv.setImageViewResource(R.id.ImageView01, util.image[shared.getInt(
                "imageState", 0)]);

        Intent intentClick = new Intent(context, update.class);
        PendingIntent pendingIntent = PendingIntent.getActivity(context, 0,
                intentClick, 0);
        rv.setOnClickPendingIntent(R.id.layout, pendingIntent);
        appWidgeManger.updateAppWidget(appWidgetId, rv);
    }
}

里面有用到一些图片资源,如果对项目有兴趣的话,

可以去下载整个项目的源码:

源码下载