羊皮书APP（Android版）开发系列（四）全屏幕延迟启动和Intent工具类

APP启动时经常会有一张启动图片，有几秒钟的展示时间，做法很简单，使用Handler的postDelayed方法即可。

• 配置全屏：在styles.xml中定义Theme，代码如下：

• 在AndroidManifest.xml文件中使用这个Theme

android:theme="@style/NoTitleFullscreen"

• 配置启动延迟代码如下：

private void delayedStart(){
        new Handler().postDelayed(new Runnable() {
            @Override
            public void run() {
                startActivity(IntentUtil.getLauncherIntent().setClass(getApplicationContext(), MainActivity.class));
                finish();
            }
        }, 3000);
    } 

• 调用方式：在Activity的onCreate方法中调用即可：

delayedStart();

• 这里有一个Intent的工具类IntentUtil.java，作用是用于启动Activity并可以传递参数。IntentUtil.java代码如下：

package cn.studyou.parchment.utils;

import android.content.Context;
import android.content.Intent;
import android.net.Uri;
import android.os.Build;
import android.os.Bundle;
import android.util.Log;
import android.widget.Toast;

/**
 * 基本功能：Intent工具类
 * 创建：王杰
 * 创建时间：16/3/7
 * 邮箱：[email protected]
 */
public class IntentUtil {
    private static final String TAG = IntentUtil.class.getSimpleName();

    public static Intent getLauncherIntent() {
        Intent intent = new Intent(Intent.ACTION_MAIN);
        intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
        intent.addCategory(Intent.CATEGORY_HOME);
        return intent;
    }
    public static void logIntent(String tag, Intent intent) {
        if (intent == null) {
            return;
        }
        StringBuffer sb = new StringBuffer();
        sb.append("\nAction:" + intent.getAction());
        sb.append("\nData:" + intent.getData());
        sb.append("\nDataStr:" + intent.getDataString());
        sb.append("\nScheme:" + intent.getScheme());
        sb.append("\nType:" + intent.getType());
        Bundle extras = intent.getExtras();
        if (extras != null && !extras.isEmpty()) {
            for (String key : extras.keySet()) {
                Object value = extras.get(key);
                sb.append("\nEXTRA: {" + key + "::" + value + "}");
            }
        } else {
            sb.append("\nNO EXTRAS");
        }
        Log.i(tag, sb.toString());
    }

    public static int sdkVersion() {
        return new Integer(Build.VERSION.SDK).intValue();
    }

    public static void startDialer(Context context, String phoneNumber) {
        try {
            Intent dial = new Intent();
            dial.setAction(Intent.ACTION_DIAL);
            dial.setData(Uri.parse("tel:" + phoneNumber));
            context.startActivity(dial);
        } catch (Exception ex) {
            Log.e(TAG, "Error starting phone dialer intent.", ex);
            Toast.makeText(context,
                    "Sorry, we couldn't find any app to place a phone call!",
                    Toast.LENGTH_SHORT).show();
        }
    }

    public static void startSmsIntent(Context context, String phoneNumber) {
        try {
            Uri uri = Uri.parse("sms:" + phoneNumber);
            Intent intent = new Intent(Intent.ACTION_VIEW, uri);
            intent.putExtra("address", phoneNumber);
            intent.setType("vnd.android-dir/mms-sms");
            context.startActivity(intent);
        } catch (Exception ex) {
            Log.e(TAG, "Error starting sms intent.", ex);
            Toast.makeText(context,
                    "Sorry, we couldn't find any app to send an SMS!",
                    Toast.LENGTH_SHORT).show();
        }
    }

    public static void startEmailIntent(Context context, String emailAddress) {
        try {
            Intent intent = new Intent(Intent.ACTION_SEND);
            intent.setType("plain/text");
            intent.putExtra(Intent.EXTRA_EMAIL,
                    new String[]{emailAddress});
            context.startActivity(intent);
        } catch (Exception ex) {
            Log.e(TAG, "Error starting email intent.", ex);
            Toast.makeText(context,
                    "Sorry, we couldn't find any app for sending emails!",
                    Toast.LENGTH_SHORT).show();
        }
    }

    public static void startWebIntent(Context context, String url) {
        try {
            Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(url));
            context.startActivity(intent);
        } catch (Exception ex) {
            Log.e(TAG, "Error starting url intent.", ex);
            Toast.makeText(context,
                    "Sorry, we couldn't find any app for viewing this url!",
                    Toast.LENGTH_SHORT).show();
        }
    }
}

• 使用方式：

startActivity(IntentUtil.getLauncherIntent().setClass(getApplicationContext(), MainActivity.class));
startActivity(IntentUtil.getLauncherIntent().setClass(getApplicationContext(), MainActivity.class).putExtra("name","name"));