1. Android Color settings
1. In the xml file
If you want to set the color, set the background property or other color properties directly. Set a color randomly, such as #000, and then click the color square on the left, and the color selector will pop up to select the color.
2. In java code
①Color.parseColor("#000");
tvShow.setBackgroundColor(Color.parseColor("#000"));
[Tip] You can configure the color value in the layout file, and then bring the color represented by "#" to the java code to use
②Color.BLACK uses the colors that come with the Color class, but they are all basic colors
tvShow.setBackgroundColor(Color.BLACK);
③ Define the Color resource file, referenced by R.color.myColor
tvShow.setBackgroundResource(R.color.myColor);
④Color.argb(a,r,g,b) method:
tvShow.setBackgroundColor(Color.argb(255, 255, 0, 0));
They are alpha, red (red), green (green), and blue (blue) four color values (ARGB). Each number takes a value from 0-255, so a color can be represented by an integer. In order to run efficiently, Android uses an integer Color class instance to represent the color when coding.
【Tip】Pass in the corresponding transparency value, red value, green value, and blue value through this method for color configuration. So we can make a simple color configurator by this method.
Second, the color configurator case
1. [Effect]
The interface design is relatively rough, I hope everyone can learn the effect and optimize the interface.
2. [Project Structure]
3. [Code]
①activity_main.xml layout file
1 <?xml version="1.0" encoding="utf-8"?> 2 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 3 xmlns:tools="http://schemas.android.com/tools" 4 android:layout_width="match_parent" 5 android:layout_height="match_parent" 6 tools:context=".MainActivity" 7 android:orientation="vertical"> 8 9 <TextView 10 android:text="请输入argb值：" 11 android:textSize="20sp" 12 android:textColor="#000" 13 android:layout_width="match_parent" 14 android:layout_height="wrap_content" 15 android:layout_margin="10dp"/> 16 17 <LinearLayout 18 android:layout_width="match_parent" 19 android:layout_height="50dp" 20 android:orientation="horizontal"> 21 <EditText 22 android:id="@+id/etA" 23 android:layout_width="0dp" 24 android:layout_weight="1" 25 android:layout_height="match_parent" 26 android:layout_margin="1dp" 27 android:hint="透明度(0-255)" 28 android:inputType="number"/> 29 30 <EditText 31 android:id="@+id/etR" 32 android:hint="红(0-255)" 33 android:layout_width="0dp" 34 android:layout_weight="1" 35 android:layout_height="match_parent" 36 android:background="#f00" 37 android:layout_margin="1dp" 38 android:gravity="center" 39 android:inputType="number"/> 40 </LinearLayout> 41 <LinearLayout 42 android:layout_width="match_parent" 43 android:layout_height="50dp" 44 android:orientation="horizontal"> 45 <EditText 46 android:id="@+id/etG" 47 android:hint="绿(0-255)" 48 android:layout_width="0dp" 49 android:layout_weight="1" 50 android:layout_height="match_parent" 51 android:background="#0f0" 52 android:layout_margin="1dp" 53 android:gravity="center" 54 android:inputType="number"/> 55 56 <EditText 57 android:id="@+id/etB" 58 android:hint="蓝(0-255)" 59 android:layout_width="0dp" 60 android:layout_weight="1" 61 android:layout_height="match_parent" 62 android:background="#00f" 63 android:layout_margin="1dp" 64 android:gravity="center" 65 android:inputType="number"/> 66 </LinearLayout> 67 68 <TextView 69 android:id="@+id/tv_show" 70 android:text="TextView" 71 android:layout_width="200dp" 72 android:layout_height="200dp" 73 android:background="#000" 74 android:layout_gravity="center" 75 android:layout_marginTop="20dp" 76 /> 77 78 <Button 79 android:id="@+id/btn" 80 android:text="确定配置" 81 android:layout_margin="20dp" 82 android:layout_width="match_parent" 83 android:layout_height="wrap_content" /> 84 </LinearLayout>
[Tip] Hint attribute in EditText: This is the prompt text in the input box. inputType property: Set the text type input in the input box, here it is set to integer type
②MainActivity.java file
1 public class MainActivity extends AppCompatActivity implements View.OnClickListener { 2 3 private EditText etA; 4 private EditText etR; 5 private EditText etG; 6 private EditText etB; 7 private TextView tvShow; 8 private Button btn; 9 10 @Override 11 protected void onCreate(Bundle savedInstanceState) { 12 super.onCreate(savedInstanceState); 13 setContentView(R.layout.activity_main); 14 15 initView(); 16 } 17 18 private void initView() { 19 etA = (EditText) findViewById(R.id.etA); 20 etR = (EditText) findViewById(R.id.etR); 21 etG = (EditText) findViewById(R.id.etG); 22 etB = (EditText) findViewById(R.id.etB); 23 tvShow = (TextView) findViewById(R.id.tv_show); 24 btn = (Button) findViewById(R.id.btn); 25 26 btn.setOnClickListener(this); 27 } 28 29 @Override 30 public void onClick(View v) { 31 switch (v.getId()) { 32 case R.id.btn: 33 submit(); 34 break; 35 } 36 } 37 38 private void submit() { 39 // validate 40 if (!etA.getText().equals("")&&!etB.getText().equals("") 41 &&!etR.getText().equals("")&&!etG.getText().equals("" )) { 42 // Check whether the value entered by the user is empty. Avoid null character cannot be converted to int exception 43 int et_a = Integer.parseInt(etA.getText().toString()); 44 int et_r = Integer.parseInt(etR.getText().toString()); 45 int et_g = Integer.parseInt(etG.getText().toString()); 46 int et_b = Integer.parseInt(etB.getText().toString()); 47 tvShow.setBackgroundColor(Color.argb(et_a, et_r, et_g, et_b )); 48 } else { 49 Toast.makeText( this, "The entered value cannot be empty" , Toast.LENGTH_SHORT).show(); 50 } 51 } 52 }