Compose加载本地图片和网络图片

加载本地图片 

Image(
    modifier = Modifier
        .fillMaxWidth()
        .height(200.dp),
    painter = painterResource(id = R.drawable.img),
    contentDescription = "描述",
    //0~1完全透明到完全不透明设置
    alpha = 1f,
    //图片拉伸或裁剪设置
    contentScale = ContentScale.Crop
)

加载本地图片通过painter属性设置图片。

alpha设置图片的透明程度，0到1从完全透明到完全不透明。

contentScale属性设置图片拉伸方式。

加载网络图片

AsyncImage(
    modifier = Modifier
        .fillMaxWidth()
        .height(200.dp),
    model = "https://pic.lvmama.com/uploads/pc/place2/2017-05-23/c362e80d-eadf-4b26-807c-629eec13bb4f.jpg",
    contentDescription = "描述",
    //图片拉伸或裁剪设置
    contentScale = ContentScale.Crop
)

加载网络图片需要引入三方库

implementation("io.coil-kt:coil-compose:2.4.0")

引用coil库后通过AsyncImage下的model属性设置图片地址。

加载网络图片需要添加网络权限

<uses-permission android:name="android.permission.INTERNET" />

完整代码：

import android.os.Bundle
import androidx.activity.ComponentActivity
import androidx.activity.compose.setContent
import androidx.compose.foundation.Image
import androidx.compose.foundation.layout.Column
import androidx.compose.foundation.layout.fillMaxSize
import androidx.compose.foundation.layout.fillMaxWidth
import androidx.compose.foundation.layout.height
import androidx.compose.material3.MaterialTheme
import androidx.compose.material3.Surface
import androidx.compose.runtime.Composable
import androidx.compose.ui.Modifier
import androidx.compose.ui.layout.ContentScale
import androidx.compose.ui.res.painterResource
import androidx.compose.ui.tooling.preview.Preview
import androidx.compose.ui.unit.dp
import coil.compose.AsyncImage
import com.cwj.composedemo.ui.theme.ComposeDemoTheme
 
class MainActivity : ComponentActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContent {
            ComposeDemoTheme {
                // A surface container using the 'background' color from the theme
                Surface(
                    modifier = Modifier.fillMaxSize(),
                    color = MaterialTheme.colorScheme.background
                ) {
                    Greeting()
                }
            }
        }
    }
}
 
@Composable
fun Greeting() {
    ImageTest()
}
 
@Composable
fun ImageTest() {
    Column {
        //加载本地图片
        Image(
            modifier = Modifier
                .fillMaxWidth()
                .height(200.dp),
            painter = painterResource(id = R.drawable.img),
            contentDescription = "描述",
            //0~1完全透明到完全不透明设置
            alpha = 1f,
            //图片拉伸或裁剪设置
            contentScale = ContentScale.Crop
        )
 
        //加载网络图片
        AsyncImage(
            modifier = Modifier
                .fillMaxWidth()
                .height(200.dp),
            model = "https://pic.lvmama.com/uploads/pc/place2/2017-05-23/c362e80d-eadf-4b26-807c-629eec13bb4f.jpg",
            contentDescription = "描述",
            //图片拉伸或裁剪设置
            contentScale = ContentScale.Crop
        )
 
    }
}
 
@Preview(showBackground = true, showSystemUi = true)
@Composable
fun GreetingPreview() {
    ComposeDemoTheme {
        Greeting()
    }
}