capitalex hat die Gist bearbeitet . Zu Änderung gehen
1 file changed, 245 insertions
MainActivity.kt(Datei erstellt)
@@ -0,0 +1,245 @@ | |||
1 | + | package com.ogletree.composecameraexample | |
2 | + | ||
3 | + | import android.content.ContentResolver | |
4 | + | import android.content.ContentValues | |
5 | + | import android.graphics.Bitmap | |
6 | + | import android.graphics.BitmapFactory | |
7 | + | import android.graphics.Matrix | |
8 | + | import android.net.Uri | |
9 | + | import android.os.Bundle | |
10 | + | import android.provider.MediaStore | |
11 | + | import androidx.activity.ComponentActivity | |
12 | + | import androidx.activity.compose.setContent | |
13 | + | import androidx.activity.result.ActivityResultLauncher | |
14 | + | import androidx.activity.result.contract.ActivityResultContracts | |
15 | + | import androidx.compose.foundation.Image | |
16 | + | import androidx.compose.foundation.background | |
17 | + | import androidx.compose.foundation.clickable | |
18 | + | import androidx.compose.foundation.layout.* | |
19 | + | import androidx.compose.material.MaterialTheme | |
20 | + | import androidx.compose.material.OutlinedButton | |
21 | + | import androidx.compose.material.Surface | |
22 | + | import androidx.compose.material.Text | |
23 | + | import androidx.compose.runtime.* | |
24 | + | import androidx.compose.ui.Alignment | |
25 | + | import androidx.compose.ui.Modifier | |
26 | + | import androidx.compose.ui.graphics.ImageBitmap | |
27 | + | import androidx.compose.ui.graphics.asImageBitmap | |
28 | + | import androidx.compose.ui.text.font.FontWeight | |
29 | + | import androidx.compose.ui.tooling.preview.Preview | |
30 | + | import androidx.compose.ui.unit.dp | |
31 | + | import com.ogletree.composecameraexample.ui.theme.ComposeCameraExampleTheme | |
32 | + | import java.text.SimpleDateFormat | |
33 | + | import java.util.* | |
34 | + | import kotlin.math.min | |
35 | + | ||
36 | + | ||
37 | + | class MainActivity : ComponentActivity() { | |
38 | + | enum class CameraPermissionStatus { NoPermission, PermissionGranted, PermissionDenied } | |
39 | + | ||
40 | + | override fun onCreate(savedInstanceState: Bundle?) { | |
41 | + | super.onCreate(savedInstanceState) | |
42 | + | ||
43 | + | val cameraPermissionStatusState = mutableStateOf(CameraPermissionStatus.NoPermission) | |
44 | + | val photoUriState: MutableState<Uri?> = mutableStateOf(null) | |
45 | + | val hasPhotoState = mutableStateOf(value = false) | |
46 | + | val resolver = applicationContext.contentResolver | |
47 | + | ||
48 | + | val requestPermissionLauncher = | |
49 | + | registerForActivityResult(ActivityResultContracts.RequestPermission()){ isGranted: Boolean -> | |
50 | + | if (isGranted) { | |
51 | + | cameraPermissionStatusState.value = CameraPermissionStatus.PermissionGranted | |
52 | + | } else { | |
53 | + | cameraPermissionStatusState.value = CameraPermissionStatus.PermissionDenied | |
54 | + | } | |
55 | + | } | |
56 | + | ||
57 | + | val takePhotoLauncher = | |
58 | + | registerForActivityResult(ActivityResultContracts.TakePicture()) { isSaved -> | |
59 | + | hasPhotoState.value = isSaved | |
60 | + | } | |
61 | + | ||
62 | + | val takePhoto: () -> Unit = { | |
63 | + | hasPhotoState.value = false | |
64 | + | ||
65 | + | val values = ContentValues().apply { | |
66 | + | val title = SimpleDateFormat("yyyyMMdd_HHmmss", Locale.US).format(Date()) | |
67 | + | put(MediaStore.Images.Media.TITLE, "Compose Camera Example Image - $title") | |
68 | + | put(MediaStore.Images.Media.DISPLAY_NAME, title) | |
69 | + | put(MediaStore.Images.Media.MIME_TYPE, "image/jpeg") | |
70 | + | put(MediaStore.Images.Media.DATE_TAKEN, System.currentTimeMillis()) | |
71 | + | } | |
72 | + | ||
73 | + | val uri = resolver.insert( | |
74 | + | MediaStore.Images.Media.EXTERNAL_CONTENT_URI, | |
75 | + | values | |
76 | + | ) | |
77 | + | takePhotoLauncher.launch(uri) | |
78 | + | photoUriState.value = uri | |
79 | + | ||
80 | + | } | |
81 | + | ||
82 | + | // Ideally these would be cached instead of reloaded | |
83 | + | val getThumbnail: (Uri?) -> ImageBitmap? = { uri -> | |
84 | + | val targetSize = 256f | |
85 | + | println("URI is $uri") | |
86 | + | uri?.let { | |
87 | + | println("Opening Input Stream") | |
88 | + | resolver.openInputStream(it) | |
89 | + | }?.let { | |
90 | + | BitmapFactory.decodeStream(it) | |
91 | + | }?.let { | |
92 | + | val height = it.height.toFloat() | |
93 | + | val width = it.width.toFloat() | |
94 | + | val scaleFactor = min(targetSize / height, targetSize / width) | |
95 | + | Bitmap.createScaledBitmap(it, (scaleFactor * width).toInt() , (scaleFactor * height).toInt(), true) | |
96 | + | }?.let { | |
97 | + | val rotation = getImageRotation(resolver, uri) | |
98 | + | Bitmap.createBitmap(it, 0, 0, it.width, it.height, Matrix().apply { postRotate(rotation.toFloat()) }, true) | |
99 | + | }?.asImageBitmap() | |
100 | + | ||
101 | + | } | |
102 | + | ||
103 | + | val getFullImage: (Uri?) -> ImageBitmap? = { uri -> | |
104 | + | uri?.let { | |
105 | + | resolver.openInputStream(it) | |
106 | + | }?.let { | |
107 | + | BitmapFactory.decodeStream(it) | |
108 | + | }?.let { | |
109 | + | val rotation = getImageRotation(resolver, uri) | |
110 | + | Bitmap.createBitmap(it, 0, 0, it.width, it.height, Matrix().apply { postRotate(rotation.toFloat()) }, true) | |
111 | + | }?.asImageBitmap() | |
112 | + | ||
113 | + | } | |
114 | + | ||
115 | + | setContent { | |
116 | + | val cameraPermissionStatus by remember { cameraPermissionStatusState } | |
117 | + | val hasPhoto by remember { hasPhotoState } | |
118 | + | var shouldShowFullImage by remember { mutableStateOf(false) } | |
119 | + | ComposeCameraExampleTheme { | |
120 | + | Box(modifier = Modifier.fillMaxSize()) { | |
121 | + | Column( | |
122 | + | modifier = Modifier.fillMaxSize(), | |
123 | + | verticalArrangement = Arrangement.Center, | |
124 | + | horizontalAlignment = Alignment.CenterHorizontally | |
125 | + | ) { | |
126 | + | TakePhotoButton( | |
127 | + | cameraPermissionStatus = cameraPermissionStatus, | |
128 | + | requestPermissionLauncher = requestPermissionLauncher, | |
129 | + | takePhoto = takePhoto | |
130 | + | ) | |
131 | + | if (hasPhoto) { | |
132 | + | val bitmap = getThumbnail(photoUriState.value) | |
133 | + | println("Is bitmap null: $bitmap") | |
134 | + | if (bitmap != null) { | |
135 | + | Image( | |
136 | + | bitmap = bitmap, | |
137 | + | contentDescription = "Thumbnail of Save Photo", | |
138 | + | modifier = Modifier.clickable { | |
139 | + | shouldShowFullImage = true | |
140 | + | } | |
141 | + | ) | |
142 | + | } | |
143 | + | } | |
144 | + | } | |
145 | + | ||
146 | + | if (shouldShowFullImage && hasPhoto) { | |
147 | + | val bitmap =getFullImage(photoUriState.value) | |
148 | + | if (bitmap != null){ | |
149 | + | Box(modifier = Modifier.fillMaxSize().clickable { | |
150 | + | shouldShowFullImage = false | |
151 | + | }){ | |
152 | + | Image( | |
153 | + | bitmap = bitmap, | |
154 | + | contentDescription = "Full image of Save Photo", | |
155 | + | modifier = Modifier.align(Alignment.Center) | |
156 | + | ) | |
157 | + | Surface( | |
158 | + | modifier = Modifier | |
159 | + | .background(MaterialTheme.colors.background) | |
160 | + | .align(Alignment.Center) | |
161 | + | .padding(8.dp) | |
162 | + | ) { | |
163 | + | Text( | |
164 | + | text = "Click to Close", | |
165 | + | style = MaterialTheme.typography.h4.copy( | |
166 | + | fontWeight = FontWeight.ExtraBold | |
167 | + | ) | |
168 | + | ) | |
169 | + | } | |
170 | + | } | |
171 | + | ||
172 | + | ||
173 | + | } else { | |
174 | + | shouldShowFullImage = false | |
175 | + | } | |
176 | + | ||
177 | + | } | |
178 | + | } | |
179 | + | } | |
180 | + | } | |
181 | + | } | |
182 | + | ||
183 | + | private fun getImageRotation(resolver: ContentResolver, uri: Uri): Int { | |
184 | + | val cursor = resolver.query(uri, arrayOf(MediaStore.Images.Media.ORIENTATION), null, null, null) | |
185 | + | var result = 0 | |
186 | + | ||
187 | + | cursor?.apply { | |
188 | + | moveToFirst() | |
189 | + | val index = getColumnIndex(MediaStore.Images.Media.ORIENTATION) | |
190 | + | result = getInt(index) | |
191 | + | close() | |
192 | + | } | |
193 | + | println("Rotation = $result") | |
194 | + | return result | |
195 | + | } | |
196 | + | ||
197 | + | } | |
198 | + | ||
199 | + | @Composable | |
200 | + | fun TakePhotoButton( | |
201 | + | cameraPermissionStatus: MainActivity.CameraPermissionStatus, | |
202 | + | requestPermissionLauncher: ActivityResultLauncher<String>, | |
203 | + | takePhoto: () -> Unit | |
204 | + | ) { | |
205 | + | OutlinedButton( | |
206 | + | onClick = { | |
207 | + | when (cameraPermissionStatus) { | |
208 | + | MainActivity.CameraPermissionStatus.NoPermission -> | |
209 | + | requestPermissionLauncher.launch(android.Manifest.permission.CAMERA) | |
210 | + | ||
211 | + | MainActivity.CameraPermissionStatus.PermissionGranted -> | |
212 | + | takePhoto() | |
213 | + | ||
214 | + | ||
215 | + | MainActivity.CameraPermissionStatus.PermissionDenied -> {} | |
216 | + | ||
217 | + | } | |
218 | + | } | |
219 | + | ) { | |
220 | + | when (cameraPermissionStatus) { | |
221 | + | MainActivity.CameraPermissionStatus.NoPermission -> | |
222 | + | Text(text = "Request Camera Permissions") | |
223 | + | ||
224 | + | MainActivity.CameraPermissionStatus.PermissionDenied -> | |
225 | + | Text(text = "Camera Permissions Have Been Denied") | |
226 | + | ||
227 | + | MainActivity.CameraPermissionStatus.PermissionGranted -> | |
228 | + | Text(text = "Take Photo") | |
229 | + | } | |
230 | + | } | |
231 | + | } | |
232 | + | ||
233 | + | ||
234 | + | @Composable | |
235 | + | fun Greeting(name: String) { | |
236 | + | Text(text = "Hello $name!") | |
237 | + | } | |
238 | + | ||
239 | + | @Preview(showBackground = true) | |
240 | + | @Composable | |
241 | + | fun DefaultPreview() { | |
242 | + | ComposeCameraExampleTheme { | |
243 | + | Greeting("Android") | |
244 | + | } | |
245 | + | } |
Neuer
Älter