Android UI基本组件

给大家介绍一下基本组件，会以代码加图片的形式，让新手更了解。

1.TextView和EditView

textview

<TextViewandroid:id="@+id/tv_csdn"android:layout_width="wrap_content"android:layout_height="wrap_content"android:layout_centerInParent="true"android:text="CSDN"android:textColor="#000"android:textSize="50dp" />

private TextView textView_csdn;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);//绑定布局文件setContentView(R.layout.activity_main);//根据id查找组件textView_csdn=findViewById(R.id.textView_csdn);}

editview

<EditTextandroid:id="@+id/editText_name"android:layout_width="match_parent"android:layout_height="wrap_content"android:hint="输入密码"android:background="#9595CE"android:textSize="40sp"android:drawableLeft="@mipmap/ic_launcher"/>

2.Toast使用

layout

<Buttonandroid:id="@+id/bt_csdn"android:layout_width="match_parent"android:layout_height="wrap_content"android:layout_centerInParent="true"android:text="欢迎来到CSDN"android:clickable="true"android:onClick="CSDN"/>

mainactivity

public void CSDN(View view) {//参数（上下文，要显示的文本内容，显示的时间（Toast.LENGTH_LONG、Toast.LENGTH_SHORT））Toast.makeText(this, "欢迎", Toast.LENGTH_SHORT).show();}

最终ui

3. ImageView

显示任意的图像，如一个图标。可以加载图像从不同来源，负责计算图像的测量，这样它就可以用于任何布局管理器
android:maxWidth；android:maxHeight；设置最大宽高
android:adjustViewBounds；保持宽高比

<ImageViewandroid:id="@+id/tv_csdn"android:layout_width="wrap_content"android:layout_height="wrap_content"android:maxWidth="200dp"android:maxHeight="200dp"android:adjustViewBounds="true"android:layout_alignParentStart="true"android:layout_alignParentLeft="true"android:layout_alignParentTop="true"/>

private ImageView iv_csdn;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);iv_csdn = (ImageView) findViewById(R.id.iv_csdn);}

4.Button 和 OnClick

1.应用场景：按钮多，Java一看就懂

//....按钮多 java一看就懂Button btn_more_button1 = (Button) findViewById(R.id.btn_more_button1);Button btn_more_button2 = (Button) findViewById(R.id.btn_more_button2);Button btn_more_button3 = (Button) findViewById(R.id.btn_more_button3);btn_more_button1.setOnClickListener(this);btn_more_button2.setOnClickListener(this);btn_more_button3.setOnClickListener(this);

2.应用场景：测试用 不适合阅读

@Overridepublic void onClick(View v) {switch (v.getId()){case R.id.btn_more_button1:Toast.makeText(this, "btn_more_button1", Toast.LENGTH_SHORT).show();break;case R.id.btn_more_button2:Toast.makeText(this, "btn_more_button2", Toast.LENGTH_SHORT).show();break;case R.id.btn_more_button3:Toast.makeText(this, "btn_more_button3", Toast.LENGTH_SHORT).show();break;}}private class MyClickListener implements View.OnClickListener{@Overridepublic void onClick(View v) {        Toast.makeText(MainActivity.this,"innerClass",Toast.LENGTH_SHORT).show();}}//........................测试用 不适合阅读

3.应用场景：按钮多 强调安卓

//***********************按钮多 强调安卓public void clickHere(View v){switch (v.getId()){case R.id.btn1:Toast.makeText(this, "btn1", Toast.LENGTH_SHORT).show();break;case R.id.btn2:Toast.makeText(this, "btn2", Toast.LENGTH_SHORT).show();break;case R.id.btn3:Toast.makeText(this, "btn3", Toast.LENGTH_SHORT).show();break;}}

5.CheckBox和RadioButton

checkbox

layout

<CheckBoxandroid:id="@+id/checkBox_java"android:layout_width="wrap_content"android:layout_height="wrap_content"android:layout_alignParentStart="true"android:layout_alignParentLeft="true"android:layout_alignParentTop="true"android:text="java" /><CheckBoxandroid:id="@+id/checkBox_c"android:layout_width="wrap_content"android:layout_height="wrap_content"android:layout_below="@id/checkBox_java"android:layout_alignParentStart="true"android:layout_alignParentLeft="true"android:text="c++" /><CheckBoxandroid:id="@+id/checkBox_python"android:layout_width="wrap_content"android:layout_height="wrap_content"android:layout_below="@id/checkBox_c"android:layout_alignParentStart="true"android:layout_alignParentLeft="true"android:text="python" />

mainactivity

public class MainActivity extends AppCompatActivity implements CompoundButton.OnCheckedChangeListener {private CheckBox checkBox_java,checkBox_c,checkBox_python;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);checkBox_java=(CheckBox) findViewById(R.id.checkBox_java);checkBox_c=(CheckBox) findViewById(R.id.checkBox_c);checkBox_python=(CheckBox) findViewById(R.id.checkBox_python);//注册事件checkBox_java.setOnCheckedChangeListener(this);checkBox_c.setOnCheckedChangeListener(this);checkBox_python.setOnCheckedChangeListener(this);}@Overridepublic void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {switch (buttonView.getId()){case R.id.checkBox_java:if (isChecked){Toast.makeText(this,"你选中了java",Toast.LENGTH_SHORT).show();}else {Toast.makeText(this,"你取消了java",Toast.LENGTH_SHORT).show();}break;case R.id.checkBox_c:if (isChecked){Toast.makeText(this,"你选中了c++",Toast.LENGTH_SHORT).show();}else {Toast.makeText(this,"你取消了c++",Toast.LENGTH_SHORT).show();}break;case R.id.checkBox_python:if (isChecked){Toast.makeText(this,"你选中了python",Toast.LENGTH_SHORT).show();}else {Toast.makeText(this,"你取消了python",Toast.LENGTH_SHORT).show();}break;}}
}

RadioButton组件
先加入一个RadioGroup，再在其中设置RadioButton

<RadioGroupandroid:layout_width="wrap_content"android:layout_height="wrap_content"android:layout_below="@id/checkBox_m"android:orientation="horizontal"><RadioButtonandroid:id="@+id/radioButton_men"android:layout_width="wrap_content"android:layout_height="wrap_content"android:checked="true"android:text="男" /><RadioButtonandroid:id="@+id/radioButton_women"android:layout_width="wrap_content"android:layout_height="wrap_content"android:text="女" /></RadioGroup>

不喜勿喷 谢谢观看