Laboratoriya ishi mavzu: Android uchun Java dasturlash tilida ilovalar yaratish Ishning maqsadi: java dasturlash tilida ilova yaratish. Nazariy qism

Amaliy qism.
Agar tizim tomonidan yo'q qilingan harakatni yana ekranda ko'rsatish kerak bo'lsa, uni to'liq qayta ishga tushirish va oldingi holatiga qaytarish kerak.
Faoliyatni dasturiy yaratish
Faoliyatning ko'rinishini shakllantirish uchun biz asosan XML belgilaridan foydalanamiz. Bu tavsiya etilgan usul va sizdan 99% foydalanadi. Ammo ba'zi hollarda, siz dasturiy ravishda faoliyatni yaratishingiz kerak bo'ladi. U erda murakkab narsa yo'q, bu umumiy rivojlanish uchun foydali bo'ladi.
Agar standart holda biz setContentView (R.layout.activity_main) usuliga XML faylini qo'shsak, uni dasturiy jihatdan yaratishda bizga bu usul kerak bo'lmaydi. O'chiring va kodni yozing:

package ru.alexanderklimov.test;

import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.LinearLayout.LayoutParams;
import android.widget.TextView;
import android.widget.Toast;

public class TestActivity extends Activity {

/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);

// bizga bu usul kerak emas

// setContentView(R.layout.activity_test);

LinearLayout layout = new LinearLayout(TestActivity.this);

layout.setId(R.id.layout_id);
LayoutParams layoutParams = new LayoutParams(LayoutParams.MATCH_PARENT,
LayoutParams.MATCH_PARENT);
layout.setLayoutParams(layoutParams);
layout.setOrientation(LinearLayout.VERTICAL);

ImageView imageView = new ImageView(TestActivity.this);

imageView.setId(R.id.image_id);
imageView.setImageResource(R.drawable.ic_launcher);
LayoutParams imageViewLayoutParams = new LayoutParams(
LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
imageView.setLayoutParams(imageViewLayoutParams);

layout.addView(imageView);

setContentView(layout);

layout.setOnClickListener(onViewClickListener);

imageView.setOnClickListener(onViewClickListener);

}

OnClickListener onViewClickListener = new OnClickListener() {

@Override
public void onClick(View v) {

int myId = v.getId();

Toast.makeText(TestActivity.this,
"ID: " + String.valueOf(myId) + " clicked",
Toast.LENGTH_LONG).show();
}
};
}
Formalash printsipi quyidagicha - biz LinearLayout ob'ektini (yoki boshqa konteynerni) yaratamiz va kerakli xususiyatlarni o'rnatamiz. Keyinchalik, biz kerakli bolalar elementlarini yaratamiz va ularning xususiyatlarini o'rnatamiz. AddView () usuli orqali bolani ota -onaga ulashni unutmang.
Labarotoriya ishlari uchun topshiriqlar.

1. "Lug'at" tipidagi rus tilidan o'zbek tiliga tarjima qilish dasturini ishlab chiqish.

2. Massivni (har qanday turdagi) kirish sifatida qabul qiladigan filtr usulini yozing va massivdan keraksiz elementlarni olib tashlash uchun apply (Object o) usuli bilan Filtr interfeysini amalga oshiring. String yoki boshqa narsalarda qanday ishlashini tekshiring.