Question

我希望我的图片视图会在4秒内定期更改，我跟着this link但代码不能正常工作。

图像视图出现在模拟器中，但图像不会间歇性地更改。我附加了我的Java代码和XML文件。

/* Java Code*/

package com.serverphone.healthyfoods;

import android.content.Intent;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.view.View;
import android.support.design.widget.NavigationView;
import android.support.v4.view.GravityCompat;
import android.support.v4.widget.DrawerLayout;
import android.support.v7.app.ActionBarDrawerToggle;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.ImageView;
import android.widget.TextView;

import java.util.logging.Handler;
import java.util.logging.LogRecord;

public class Menu1 extends AppCompatActivity implements NavigationView.OnNavigationItemSelectedListener {
    ImageView iv;
    TextView tv;
    int i = 0;
    int imageArray[] = {R.drawable.chicken_curry1,R.drawable.chicken_biriyani,R.drawable.paneer_butter};
    String textArray[] = {"Chicken curry","Chicken Biriyani","Paneer Butter Masala"};

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_menu1);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);
        getSupportActionBar().setTitle("Main Menu");
        tv=(TextView)findViewById(R.id.info_text);
        iv=(ImageView)findViewById(R.id.image);

        Runnable r = new Runnable() {
            @Override
            public void run() {
                iv.setImageResource(imageArray[i]);
                i++;
                if(i >= imageArray.length)
                    i=0;
                //iv.postDelayed(r,4000);
            }
        };
        iv.postDelayed(r,4000);  

        /*FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
        fab.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
                        .setAction("Action", null).show();
            }
        });*/

        DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
                this, drawer, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close);
        drawer.setDrawerListener(toggle);
        toggle.syncState();

        NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view);
        navigationView.setNavigationItemSelectedListener(this);
    }

    @Override
    public void onBackPressed() {
        DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        if (drawer.isDrawerOpen(GravityCompat.START)) {
            drawer.closeDrawer(GravityCompat.START);
        } else {
            super.onBackPressed();
        }
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu1, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();
        //noinspection SimplifiableIfStatement
        if (id == R.id.action_settings) {
            return true;
        }
        return super.onOptionsItemSelected(item);
    }

    @SuppressWarnings("StatementWithEmptyBody")
    @Override
    public boolean onNavigationItemSelected(MenuItem item) {
        // Handle navigation view item clicks here.
        int id = item.getItemId();

        if (id == R.id.iov) {
            // Handle the camera action
            Intent i=new Intent(Menu1.this,InstantOrderVeg.class);
            startActivity(i);
        } else if (id == R.id.ionv) {
            Intent i=new Intent(Menu1.this,InstantOrderNveg.class);
            startActivity(i);
        } else if (id == R.id.alaca) {
            Intent i=new Intent(Menu1.this,AlaCarte.class);
            startActivity(i);
        } else if (id == R.id.cater) {
            Intent i=new Intent(Menu1.this,Catering.class);
            startActivity(i);
        } else if (id == R.id.cont) {
            Intent i=new Intent(Menu1.this,ContactUs.class);
            startActivity(i);
        }

        DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        drawer.closeDrawer(GravityCompat.START);
        return true;
    }
}

<!-- XML file-->

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:card_view="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent" android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    android:paddingBottom="@dimen/activity_vertical_margin"
    app:layout_behavior="@string/appbar_scrolling_view_behavior"
    tools:showIn="@layout/app_bar_menu1" tools:context="com.serverphone.healthyfoods.Menu1">


    <android.support.v7.widget.CardView
        android:id="@+id/card_view"
    card_view:cardElevation="10dp"
    android:layout_centerHorizontal="true"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    card_view:cardBackgroundColor="#E8EAF6"

    card_view:cardCornerRadius="4dp">
    <RelativeLayout
        android:layout_width="match_parent"
    android:layout_height="match_parent">
    <TextView
        android:id="@+id/info_text"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:text="\t\t\t\t\t\t\t\t\t\tChicken Curry"
        android:textSize="30dp"
        android:textStyle="italic"
    />

    <ImageView
        android:id="@+id/image"
    android:layout_below="@id/info_text"
    android:layout_width="match_parent"
    android:layout_height="200dp"
    android:layout_marginTop="20dp"
    android:scaleType="fitXY"
    android:src="@drawable/chicken_curry1"/>
</RelativeLayout>

    </android.support.v7.widget.CardView>

</RelativeLayout>

Answer 1

从oncreate（）开始第一次

public void onCreate(Bundle b){

handler.postDelayed(changeImage, 1000);

}`

Handler handler = new Handler();

Runnable changeImage = new Runnable（）{

@Override
public void run(){
    if(flag>1)
       handler.removeCallbacks(changeImage);
    else{
       iv.setImageResource(v[flag++]);
       handler.postDelayed(changeImage, 1000);
    }
}

};

Answer 2

尝试使用AsyncTask。它允许轻松地在线程中进行UI更改。这可能对你有帮助。

定期更改图像视图

2 个答案: