Chapter 4 - HarmonyOS Hongmeng Development: Write the second page with Java code in 3 minutes

Author: Li Yuechun, founder of Kongyi Academy and Programming Cafe.

For free system learning, please go to: https://chengxuka.com

In the previous section, we wrote a page containing text and buttons in XML. In this section we use code to write the second page.

• Open src/main/java/com/example/myapplication/slice/MainAbilitySlice.javathe file and copy the following code into it.

package com.example.myapplication.slice;

import com.example.myapplication.ResourceTable;
import ohos.aafwk.ability.AbilitySlice;
import ohos.aafwk.content.Intent;

import ohos.agp.colors.RgbColor;
import ohos.agp.components.DependentLayout;
import ohos.agp.components.Text;
import ohos.agp.components.element.ShapeElement;
import ohos.agp.utils.Color;
import ohos.agp.components.DependentLayout.LayoutConfig;

public class MainAbilitySlice extends AbilitySlice {
    @Override
    public void onStart(Intent intent) {
        super.onStart(intent);

        // 声明布局
        DependentLayout myLayout = new DependentLayout(this);

        // 设置布局宽高
        myLayout.setWidth(LayoutConfig.MATCH_PARENT);
        myLayout.setHeight(LayoutConfig.MATCH_PARENT);

        // 设置布局背景为白色
        ShapeElement background = new ShapeElement();
        background.setRgbColor(new RgbColor(255, 255, 255));
        myLayout.setBackground(background);

        // 创建一个文本
        Text text = new Text(this);
        text.setText("www.chengxuka.com");
        text.setWidth(LayoutConfig.MATCH_PARENT);
        text.setTextSize(100);
        text.setTextColor(Color.BLACK);

        // 设置文本的布局
        DependentLayout.LayoutConfig textConfig = new DependentLayout.LayoutConfig(LayoutConfig.MATCH_CONTENT, LayoutConfig.MATCH_CONTENT);
        textConfig.addRule(LayoutConfig.CENTER_IN_PARENT);
        text.setLayoutConfig(textConfig);
        myLayout.addComponent(text);

        super.setUIContent(myLayout); // 加载XML布局
    }
}

• Run the project to see the effect.

Entry Series

• HarmonyOS Hongmeng development: development environment DevEco Studio installation
• Chapter 2 - HarmonyOS Hongmeng Development: Starting from Hello Word
• Chapter 3 - HarmonyOS Hongmeng Development: Write the first page with XML layout in 3 minutes
• Chapter 4 - HarmonyOS Hongmeng Development: Write the second page with Java code in 3 minutes
• Chapter 5 - HarmonyOS development: page jump in 3 minutes