Question

我是android studio的新手，我制作了一个适用于所有android的应用程序，但在android 6.0以下版本无法正常工作，并且错误状态为“膨胀欢迎活动” 因此，我提供了我的欢迎活动屏幕代码以及gradle代码。请进行检查，如果有人能找到错误，那就太好了。预先感谢

欢迎活动代码：

package com.divesh.sliderapp;

import android.content.Context;
import android.content.Intent;
import android.graphics.Color;
import android.os.Build;
import android.os.Bundle;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.support.v7.app.AppCompatActivity;
import android.text.Html;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.view.Window;
import android.view.WindowManager;
import android.widget.Button;
import android.widget.LinearLayout;
import android.widget.TextView;

public class WelcomeActivity extends AppCompatActivity {
private ViewPager viewPager;
private MyViewPagerAdapter myViewPagerAdapter;
private LinearLayout dotsLayout;
private TextView[] dots;
private int[] layouts;
private Button btnSkip, btnNext;
private PrefManager prefManager;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    // Checking for first time launch - before calling setContentView()
    prefManager = new PrefManager(this);
    if (!prefManager.isFirstTimeLaunch()) {
        launchHomeScreen();
        finish();
    }

    // Making notification bar transparent
    if (Build.VERSION.SDK_INT >= 21) {
        getWindow().getDecorView().setSystemUiVisibility(View.SYSTEM_UI_FLAG_LAYOUT_STABLE | View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN);
    }

    setContentView(R.layout.activity_welcome);

    viewPager = (ViewPager) findViewById(R.id.view_pager);
    dotsLayout = (LinearLayout) findViewById(R.id.layoutDots);
    btnSkip = (Button) findViewById(R.id.btn_skip);
    btnNext = (Button) findViewById(R.id.btn_next);


    // layouts of all welcome sliders
    // add few more layouts if you want
    layouts = new int[]{
            R.layout.welcome_slide1,
            R.layout.welcome_slide2,
            R.layout.welcome_slide3,
            R.layout.welcome_slide4};

    // adding bottom dots
    addBottomDots(0);

    // making notification bar transparent
    changeStatusBarColor();

    myViewPagerAdapter = new MyViewPagerAdapter();
    viewPager.setAdapter(myViewPagerAdapter);
    viewPager.addOnPageChangeListener(viewPagerPageChangeListener);

    btnSkip.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            launchHomeScreen();
        }
    });

    btnNext.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            // checking for last page
            // if last page home screen will be launched
            int current = getItem(+1);
            if (current < layouts.length) {
                // move to next screen
                viewPager.setCurrentItem(current);
            } else {
                launchHomeScreen();
            }
        }
    });
}

private void addBottomDots(int currentPage) {
    dots = new TextView[layouts.length];

    int[] colorsActive = getResources().getIntArray(R.array.array_dot_active);
    int[] colorsInactive = getResources().getIntArray(R.array.array_dot_inactive);

    dotsLayout.removeAllViews();
    for (int i = 0; i < dots.length; i++) {
        dots[i] = new TextView(this);
        dots[i].setText(Html.fromHtml("&#8226;"));
        dots[i].setTextSize(35);
        dots[i].setTextColor(colorsInactive[currentPage]);
        dotsLayout.addView(dots[i]);
    }

    if (dots.length > 0)
        dots[currentPage].setTextColor(colorsActive[currentPage]);
}

private int getItem(int i) {
    return viewPager.getCurrentItem() + i;
}

private void launchHomeScreen() {
    prefManager.setFirstTimeLaunch(false);
    startActivity(new Intent(WelcomeActivity.this, MainActivity.class));
    finish();
}

//  viewpager change listener
ViewPager.OnPageChangeListener viewPagerPageChangeListener = new ViewPager.OnPageChangeListener() {

    @Override
    public void onPageSelected(int position) {
        addBottomDots(position);

        // changing the next button text 'NEXT' / 'GOT IT'
        if (position == layouts.length - 1) {
            // last page. make button text to GOT IT
            btnNext.setText(getString(R.string.start));
            btnSkip.setVisibility(View.GONE);
        } else {
            // still pages are left
            btnNext.setText(getString(R.string.next));
            btnSkip.setVisibility(View.VISIBLE);
        }
    }

    @Override
    public void onPageScrolled(int arg0, float arg1, int arg2) {

    }

    @Override
    public void onPageScrollStateChanged(int arg0) {

    }
};

/**
 * Making notification bar transparent
 */
private void changeStatusBarColor() {
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
        Window window = getWindow();
        window.addFlags(WindowManager.LayoutParams.FLAG_DRAWS_SYSTEM_BAR_BACKGROUNDS);
        window.setStatusBarColor(Color.TRANSPARENT);
    }
}

/**
 * View pager adapter
 */
public class MyViewPagerAdapter extends PagerAdapter {
    private LayoutInflater layoutInflater;

    public MyViewPagerAdapter() {
    }

    @Override
    public Object instantiateItem(ViewGroup container, int position) {
        layoutInflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);

        View view = layoutInflater.inflate(layouts[position], container, false);
        container.addView(view);

        return view;
    }

    @Override
    public int getCount() {
        return layouts.length;
    }

    @Override
    public boolean isViewFromObject(View view, Object obj) {
        return view == obj;
    }


    @Override
    public void destroyItem(ViewGroup container, int position, Object object) {
        View view = (View) object;
        container.removeView(view);
    }
}

}

成绩文件：

    // Top-level build file where you can add configuration options common to all sub-projects/modules.

buildscript {

    repositories {
        mavenCentral()
        jcenter()
        google()



    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.1.2'
        classpath 'com.google.gms:google-services:4.0.1'


        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

allprojects {
    repositories {
        google()
        jcenter()
    }
}

task clean(type: Delete) {
    delete rootProject.buildDir
}

另一个Gradle文件：

// Top-level build file where you can add configuration options common to all sub-projects/modules.

buildscript {

    repositories {
        mavenCentral()
        jcenter()
        google()



    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.1.2'
        classpath 'com.google.gms:google-services:4.0.1'


        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

allprojects {
    repositories {
        google()
        jcenter()
    }
}

task clean(type: Delete) {
    delete rootProject.buildDir
}

清单文件：

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.divesh.sliderapp">
    <uses-permission android:name="android.permission.INTERNET" />
    <uses-permission android:name="com.android.vending.BILLING"/>

    <application
        android:name=".sliderapp"
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@drawable/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".WelcomeActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <activity
            android:name=".MainActivity"
            android:label="@string/title_activity_welcome"
            android:theme="@style/AppTheme.NoActionBar" />
        <activity android:name=".payment" />
        <activity android:name=".Information" />
        <activity android:name=".PaymentSuccess" />
        <activity android:name=".PaymentError"></activity>
    </application>

</manifest>

Answer 1

       in your code -  if (Build.VERSION.SDK_INT >= 21) {
                getWindow().getDecorView().setSystemUiVisibility(View.SYSTEM_UI_FLAG_LAYOUT_STABLE | View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN);
            }

    &&

     if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) 

    you defined here API LEVEL >= 21 so is crashing below API level.

ADD this code to stop  crashing.

private void setUpActionBar() {
    // Make sure we're running on Honeycomb or higher to use ActionBar APIs
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
        ActionBar actionBar = getActionBar();
        actionBar.setDisplayHomeAsUpEnabled(true);
    }
}

我的应用在android 6.0以下崩溃的原因是什么？

1 个答案: